Browse Other O Word Lengths
9-Letter O Words by Ending Letter
All 1,776 9-Letter Words Starting With O
oakenshawA grove of oaks.oakleavesplural of oakleafoarfishesplural of oarfishoarswomanA female oarsman.oasislessLacking an oasis.oasislikeResembling or characteristic of an oasis.oasthouseAlternative spelling of oast house.oatenmeal(obsolete) oatmealoathboundBound by an oath.obacunone(organic chemistry) A natural compound present in citrus fruits that has antiinflammatory and anticancer propertiesobatoclaxAn experimental drug candidate for the treatment of various cancers.obbligato(music) An obbligato section; a prominent countermelody, often written to be played or sung above the principal theme (in a higher pitch range).obclavateInversely clavate; thicker at the base.obconicalAlternative form of obconic.obcordate(botany, of a leaf) Of a reversed cordate shape; heart-shaped but attached to the stalk by the pointed end.obdeltate(botany) In the shape of an equilateral triangle with the apex at the base.obdeltoid(botany, of leaves) Triangular and attached to the stem via a tip.obduction(largely obsolete) An autopsy.obdurancehardness; stubbornnessobduratorA rigid part of a sigmoidoscope or similar deviceobedienceThe quality of being obedient.obediencyObedience, the quality of being obedient.obeisanceDemonstration of an obedient attitude, especially by bowing deeply; a deep bow which demonstrates such an attitude.obeisancyAlternative form of obeisance.obeisauntObsolete form of obeisant.obeliscalresembling, or pertaining to, an obelisk.obeliscarIn the form of an obelisk.obestatin(biochemistry) An oligopeptide sequence, present in ghrelin, that binds to a specific orphan receptorobeyingly(rare) obedientlyobeysauntObsolete form of obeisant.obfuscateTo make dark; to overshadow.obfuscousdark; obscure; shadowyobidoximeAn oxime used to treat nerve gas poisoning.objectantSynonym of objector.objectify(ambitransitive) To make (something, such as an abstract idea) possible to be perceived by the senses.objectingpresent participle and gerund of objectobjectionThe act of objecting.objectismAn approach to poetry in which the poet is regarded as just one object among the other objects in existence, rather than a subject through which they are mediated.objectistAn objectivist.objectiveOf or relating to a material object, actual existence or reality.objectizeTo turn into, or treat as, an object; to objectify.objectorsplural of objectorobjectrix(chiefly law, rare) A woman who objects; a female objector; compare objectress.objectualRelating to, or represented as an objectobjicient(obsolete) One who makes objection; an objector.objurgate(transitive) To rebuke or scold strongly.oblationsplural of oblationoblectate(obsolete, rare) To delight; to please greatly.obligableAcknowledging, or complying with, obligation; trustworthy.obligancyThe status of being an obligant.obligantsplural of obligantobligatedsimple past and past participle of obligateobligatee(government) A person who is obligated by law to do somethingobligatesthird-person singular simple present indicative of obligateobligator(law) One who establishes an obligation under lawobligatosplural of obligatoobligatum(logic) That which is, or must be, granted.obligedlygratefully; indebtedlyobliquelyIn an oblique manner; sideways.obliquityThe quality of being oblique in direction, deviating from the horizontal or vertical; or the angle created by such a deviation.obliviate(transitive) To forget; to wipe from existence.oblivious(usually with to or of) Lacking awareness; unmindful; unaware, unconscious of.oblocutor(archaic) A gainsayer; a critic.oblongata(anatomy) Clipping of medulla oblongata.oblongateSynonym of oblong.oblongishSomewhat oblong in shape.obloquialOf or relating to obloquy.obnoxiety(obsolete, rare) obnoxiousnessobnoxiousExtremely offensive or unpleasant; very annoying, contemptible, or odious.obomegoid(rare, archaic, zoology) Obversely omegoid.obovatelyIn an obovate manner.oboyerite(mineralogy) A triclinic mineral containing hydrogen, lead, oxygen, and tellurium.obreption(Scots law, obsolete) Act of obtaining gifts of escheat by fraud or surprise.obruption(geology, taphonomy) Quick burial.obscenelyIn an obscene manner; vulgarly.obscenist(rare) One who behaves obscenely, or produces obscene works.obscenity(countable) Something that is obscene.obscurantActing or tending to confound, obfuscate, or obscure.obscurate(transitive) To obscure.obscurelyIn an obscure manner.obscurestsuperlative form of obscure: most obscureobscurifyto make obscureobscuringpresent participle and gerund of obscureobscuristOne who creates ambiguous works.obscurity(literary) Darkness; the absence of light.obsecrate(transitive) To beseech; to supplicate; to implore.obsequent(geology) Facing the opposite way of what would be expected, for example, a stream flowing towards higher elevation.obsequialRelating to an obsequy or funeral rite.obsequies(plural only) Funeral rites.obsequityThe state of being obsequious; unctuousnessobservantAlert and paying close attention; watchful.observersplural of observerobservingpresent participle and gerund of observeobsessingpresent participle and gerund of obsessobsessionThe quality of being obsessed.obsessiveProne to cause obsession.obsessoid(psychiatry, of personality) Showing resemblance to obsessive-compulsive disorder.obsidiansplural of obsidianobsidious(rare) besieging; besetting, obsessionalobsignate(obsolete) To seal or ratify.obsolesceTo become obsolete.obsoletedsimple past and past participle of obsoleteobsoleter(nonstandard) comparative form of obsolete: more obsoleteobsoletor(rare) Something which obsoletes something else.obsonator(obsolete or historical) A caterer, a manciple.obstaclesplural of obstacleobstetricOf or relating to obstetrics (the care of women during and after pregnancy).obstetrix(formal) A midwife.obstinacyThe state, or an act, of stubbornness or doggedness.obstinant(proscribed) Obstinate.obstinateStubbornly adhering to an opinion, purpose, or course, usually with implied unreasonableness; persistent.obstinentMisspelling of obstinant.obstipate(medicine) To induce severe constipation through an intestinal blockageobstructsthird-person singular simple present indicative of obstructobstruentCausing obstruction; blocking up.obstupefy(obsolete) To stupefy.obtainingpresent participle and gerund of obtainobtenance(rare) the act of obtaining somethingobtensionobtaining; obtainmentobtention(rare, sciences, law) The act of obtaining.obtestingpresent participle and gerund of obtestobtrudingpresent participle and gerund of obtrudeobtrusionAn interference or intrusion.obtrusiveOf a person: overly assertive, bold, or domineering; pushy; also, ostentatious.obtundentA substance which sheathes a part, or blunts irritation, usually some bland, oily, or mucilaginous matter; – nearly the same as demulcent.obtundingpresent participle and gerund of obtundobtundity(rare, often medicine) The state or characteristic of having dulled senses or limited awareness.obturacleAlternative form of obturaculum.obturatesthird-person singular simple present indicative of obturateobturator(surgery) An object used to obstruct a hole, such as a fissure of the palate.obumbrate(zoology, rare) Lying under some projecting part, like the abdomen of certain spiders.obvallate(obsolete, rare) To surround with, or as with, a wall.obvention(obsolete) The act of happening incidentally; that which happens casually; an incidental advantage; an occasional offering.obversant(obsolete) conversant; familiar or in the know about a certain topic.obversely(botany) In an obverse manner.obversionThe act of turning toward or downward.obvertingpresent participle and gerund of obvertobviatingpresent participle and gerund of obviateobviationThe act of obviating; deterrence or prevention.obviative(linguistics) Relating to such a referent or grammatical marker.obviosityThe quality of being obvious.obviouslyIn an obvious or clearly apparent manner.obvolutedAlternative form of obvolute.obvolventCurved downward or inward.ocarinistSomeone who plays the ocarina.occasionsplural of occasionoccerenceMisspelling of occurrence.occiduousWestern; occidental.occipital(anatomy) Of, pertaining to, or located within or near the occiput (back of the head) or the occipital bone.occludantSomething that occludes.occludentServing to occlude or close.occludingpresent participle and gerund of occludeocclusionThe process of occluding, or something that occludes.occlusiveThat tends to occlude.occultate(transitive) To make occult or hidden.occultingpresent participle and gerund of occultoccultism(philosophy) The study of the supernaturaloccultistA person who practises or studies occultism; a practitioner of, or person learned in, the occult.occultiveRelated to or involving the occult or secret knowledge.occultureThe appropriation by a subculture of occult themes (New Age, etc.) in opposition to the dominant culture.occupableAlternative form of occupiable.occupancyThe act of occupying, the state of being occupied or the state of being an occupant or tenant.occupantsplural of occupantoccupiersplural of occupieroccupyingpresent participle and gerund of occupyoccurableCapable of happening.occuranceMisspelling of occurrence.occurenceMisspelling of occurrence.occurrentCurrent, actual, occurring.occurringpresent participle and gerund of occuroccursion(obsolete, literal or figurative) A meeting or striking together; a clash or collision.oceanariaplural of oceanariumoceanautsplural of oceanautoceanitesplural of oceaniteoceanitid(zoology) Any member of the family Oceanitidae of southern storm petrels or Austral storm petrels.oceanlessWithout an ocean.oceanlikeRelating to an ocean in vastness or composition.oceansideLocated on the coast of an ocean.oceanviewOverlooking the oceanoceanwardToward the ocean.oceanwideSpanning the whole oceanoceanwise(rare) Towards or along an ocean.ocellatedOf, pertaining to, resembling or having an ocellus.ochlagogy(rare) Manipulation of a mob by use of inflammatory rhetoric, casting opprobrium, and by appeal to the lowest common denominator generally; extreme and wholly unscrupulous demagogy; the practice of an ochlagogue.ochlocratAn adherent of the principle of ochlocracy; an advocate of mob rule.ochlologythe psychology of crowds or mobsochodaeid(entomology, taxonomy) Any beetle in the family Ochodaeidae.ochotonid(zoology) Any member of the family Ochotonidae, the pikas.ocinaplon(pharmacology) A particular kind of anxiolytic pyrazolopyrimidine drug.ocotillosplural of ocotillooctabasic(chemistry, of an acid) containing eight replaceable hydrogen atomsoctabromo(organic chemistry, in combination) Eight bromine atoms in a moleculeoctacaine(pharmacology) An anesthetic drug.octachordA musical instrument with eight strings.octadecyl(organic chemistry) Any of very many isomeric univalent hydrocarbon radicals, C₁₈H₃₇, formally derived from an octadecane by the loss of a hydrogen atomoctadiene(organic chemistry) Any of several isomeric dienes having eight carbon atomsoctaedralArchaic form of octahedral.octaedronAlternative spelling of octahedron.octaethyl(organic chemistry, in combination) Eight ethyl groups in a moleculeoctagonal(geometry) Shaped like an octagon, in having eight sides and eight angles.octahedraplural of octahedronoctalogueA series of eight statements.octamericOf or pertaining to an octamer.octameterA line of verse containing eight metrical feetoctamoxinA hydrazine drug formerly used as an antidepressant.octanoate(organic chemistry) Any salt or ester of octanoic acid.octaoxide(inorganic chemistry) Alternative form of octoxide.octaploidAlternative form of octoploid.octapolarThat employs eight electrodesoctarchicOf or relating to octarchy.octastichA poem or strophe of eight verses or lines.octastyle(architecture) Having eight columns in the front row (of a portico etc.)octateuchA collection of eight books; especially, the first eight books of the Old Testament.octathlon(athletics) A sporting event consisting of eight different sports or contests.octatomic(chemistry) Having eight atoms in each moleculeoctatonic(music) Containing eight notes.octavated(music, rare, of an instrument) Altered to sound a pitch one octave lower than its usual range.octaviate(music, rare) To octavate.octennialOccurring every eight years.octennium(rare) An eight-year period.octeocyteMisspelling of osteocyte.octiamond(geometry) A polyiamond made up of eight triangles.octillion(US, modern British and Australia, short scale) A thousand trillion trillion, a billion billion billion: 1 followed by 27 zeros, 10²⁷.octoalloyAn alloy of eight metals (gold, silver, copper, lead, zinc, tin, iron, and antimony or mercury), formerly used in India for making idols.octochordAlternative form of octachord.octocoral(marine biology) An anthozoan of the subclass Alcyonaria, having eight-branched tentacles and eight septa.octodrine(pharmacology) A particular kind of stimulant drug.octofinalAlternative form of octafinal.octogonalObsolete form of octagonal.octomericMisspelling of octameric.octophone(music) A modern stringed instrument intended to be able to play the tone combinations of the tenor guitar, tenor banjo, ukulele, taro-patch fiddle, tiple, mandolin, mandola and mandocello.octoploid(genetics) having eight complete sets of chromosomes in a single celloctopodalOctopoid, octopuslike.octopodanRelating to cephalopod molluscs of the order Octopoda.octopodes(rare) plural of octopusoctopodicResembling an octopus; octopuslike.octopodid(zoology) Any octopus in the family Octopodidae.octopolarRelating to an octopole.octopusesplural of octopusoctopusic(uncommon) Octopuslike.octopussy(childish or endearing) An octopus.octoroonsplural of octoroonoctospore(biology) A carpospore (one of eight) produced by red algae of the family Bangiaceaeoctostyle(architecture) A temple or portico with eight columns in front.octothorn(rare) Alternative form of octothorpe, the symbol #.octothorpAlternative spelling of octothorpe.octuplingpresent participle and gerund of octupleoctupolarOf or pertaining to an octupole.octylated(organic chemistry) Modified by addition of an octyl groupocularistSomeone who specializes in the fabrication and fitting of ocular prostheses for people who have lost an eye or eyes due to trauma or illness.ocularityA measure of the number of eyes needed to see something, i.e. monocular or binocular.oculariumA slit in a helmet through which the wearer could see.oculesicsThe study of eye contact as a form of body language.oculiformHaving the shape of an eyeoculisticRelating to oculism.ocypodian(zoology, archaic) A member of the crab family Ocypodidae.odalisque(art) An erotic painting of a woman, usually nude, reclining in a luxurious or exotic setting.oddnessesplural of oddnessoddsboardA board displaying the odds (or lines) for sports betting.oddsmakerA person who sets odds for gambling.odiferous(sometimes proscribed) Odoriferous; smellyodobenineOf, or pertaining to, a walrus.odometersplural of odometerodometricAlternative form of odometrical.odonatistOne who studies dragonflies or damselflies.odontagra(obsolete) An instrument for drawing teeth.odontalgyArchaic form of odontalgia.odorament(archaic) Something which gives off a scent; an odoriferous substance.odoratingDiffusing odour or scent; fragrant or odorous.odorative(not comparable) Relating to the sense of smell.odorizingpresent participle and gerund of odorizeodorosideA particular steroid glycoside.odorosityThe quality or degree of being odorous.odorouslyIn an odorous manner.odorprintAlternative form of odourprint.odorproofResistant to odors.odorscapeAlternative form of odourscape.odortaxis(nematology) The movement of an organism with respect to, usually towards, a volatile airborne chemical.odourlessHaving no odour.odoursomeAlternative form of odorsome.odourtypeAlternative form of odortype.odycoloneEye dialect spelling of eau de Cologne.oeconomus(ecclesiastical) A married priest (chiefly Orthodox Christian and Uniate usage), as opposed to a hieromonk.oecumenicArchaic form of ecumenic.oedematicCharacteristic of an oedema, pertaining to oedemata; oedematous.oedemerid(zoology) Any beetle in the family Oedemeridae.oedipallyIn a manner related to an Oedipus complex. Adverb form of oedipal.oedipodid(zoology) Any grasshopper in the family Oedipodidae, now considered to be the acridid subfamily Oedipodinae.oedometer(geology) A device used for measuring the consolidation properties of soiloeilladesplural of oeilladeoenanthalAlternative form of enanthal.oenanthicAlternative form of enanthic.oenaphileMisspelling of oenophile.oenocyticOf or relating to oenocytes.oenogarumgarum diluted with wineoenologue(rare) An oenologist.oenomancydivination by studying wineoenomaniaMorbid desire for wine; dipsomania; alcoholism.oenometerAn alcoholometer.oenophileA person who has a fondness or appreciation for wine.oenophilySynonym of oenophilia.oesophagiplural of oesophagusoestrogen(Commonwealth) Alternative spelling of estrogen.oestruateTo be in heat (state of sexual receptivity).offchanceAlternative form of off chance.offcomingcoming or casting off; retiring, shedding, detaching or emittingoffcumden(Yorkshire) Someone not from the area; an incomer, an outsider.offcutterAlternative form of off cutter.offenciveObsolete form of offensive.offendersplural of offenderoffendingpresent participle and gerund of offendoffendourObsolete form of offender.offension(obsolete) Assault; attack, offensive; offense.offensiveCausing offense; arousing a visceral reaction of disgust, anger, hatred, sadness, or indignation.offerableCapable of being offeredofferingsplural of offeringofferlessWithout offeroffertory(Christianity, historical) A linen or silken cloth anciently used in various ceremonies connected with the administration of the Eucharist.offerture(obsolete) offer; proposaloffglidesplural of offglideoffhandedIn a casual or curt style, without preparation or thought; impromptu, offhand.officefulThe amount that fills an office.officeredsimple past and past participle of officerofficerlyLike or befitting an officer.officetel(South Korea) a multi-purpose building in Korea with both residential and commercial unitsofficialsplural of officialofficiantA person who officiates at a religious ceremony (in Christianity, at any ceremnoy other than the Eucharist).officiaryOf or pertaining to an office or an officer; official.officiate(intransitive, transitive) To perform the functions of some office.officinal(dated) Medicinal.officiousOffensively intrusive or interfering in offering advice and services.offloadedsimple past and past participle of offloadoffloaderOne who, or that which, offloads.offprintsplural of offprintoffretite(mineralogy) A hexagonal prismatic form of zeoliteoffroaderAlternative form of off-roader.offsaddle(transitive, chiefly South Africa) To unsaddle; remove the saddle from.offscreenExisting or happening outside the frame of the cinema or television screenoffseasonAlternative form of off-season.offsetterOne who, or that which, offsets.offshootsplural of offshootoffshorerAn organization that sends work abroad, hiring foreign labour as a substitute for local labour.offspringA person's daughter or son; a person's child.offstreamNot located on a streambed.offuscateObsolete form of obfuscate.ofloxacin(pharmacology) A fluoroquinolone antibiotic C₁₈H₂₀FN₃O₄ composed of equal quantities of levofloxacin and dextrofloxacin, that is a broad-spectrum antibacterial agent that is used in topical solution for otic or ophthalmic use or is administered orally or intravenously for other uses.oftenness(rare) The quality of happening often; frequency.oftentide(obsolete) Often; frequently.oftentime(chiefly US, uncommon) (elsewhere, archaic) Synonym of oftentimes.oftwhiles(archaic) Often; oftentimes.oganessonThe chemical element (symbol Og) with atomic number 118. It is the heaviest known element. Highly radioactive, it does not occur naturally. Originally expected to be a noble gas, it is now predicted to be a reactive metallic solid, and a semiconductor or a post-transition metal.ogdohedryThe condition of being ogdohedralogglesomeAwesome; dreadful.ohmicallyBy means of ohmic heating, the process by which the passage of an electric current through a conductor releases heat.ohnologue(genetics) One of a pair of paralogous sequences that result from complete genome duplication.ohunkakanTraditional Sioux evening stories.oichomage(sumo) The elaborate hairstyle, resembling a gingko leaf, worn by sekitori during bouts and on ceremonial occasions.oikeiosis(philosophy, ethics) The perception of something as being one's own, or belonging to oneself.oikocryst(geology) An enclosing crystal in a poikilitic fabric.oikophobeOne who suffers from oikophobia, especially one who identifies with a global group rather than feelings of patriotism or chauvinism.oilfieldsplural of oilfieldoiligarch(informal, derogatory) A member of the ruling class that obtains their power from control of the oil industry.oilocracyA country whose capital comes mostly or largely from petroleum reserves.oilometerSynonym of oleometer (“instrument for determining the weight and purity of oil”).oilstonesplural of oilstoneoinomancyA form of divination conducted by examining patterns in wine.oinomaniaArchaic form of oenomania.ointmentsplural of ointmentoioxenous(biology, of a parasite) Having a single species of hostojuelaite(mineralogy) A monoclinic-prismatic greenish yellow mineral containing arsenic, hydrogen, iron, oxygen, and zinc.okeydokeyAlternative form of okey-dokey.okupukupuAlternative form of kupukupu.okuriashi(sumo) A situation in which a rikishi accidentally steps out of ring whilst carrying his opponent out, his opponent thus winning.okurigake(sumo) A kimarite in which the attacker hooks his legs behind one of his opponent's and pulls it towards himself from behind, toppling his opponent forward.okurigana(orthography) In the Japanese language, the kana which follow a stem written with kanji, which record how that stem is inflected, and guides recognition of the appropriate kun'yomi reading (word stem associated with the kanji); for example, く (ku) and かべる (kaberu) in 浮(う)く (uk-u, “to float”, intransitive) and 浮(う)かべる (uk-aberu, “to float”, transitive), or む (mu) and きる (kiru) in 生(う)む (umu, “to birth”) and 生(い)きる (ikiru, “to live”). Perhaps analogous to -st, -nd in English 1st (first), 2nd (second).okurinage(sumo) A kimarite in which the attacker circles behind his opponent and throws him forward or to the side and down.oldermost(US, dialectal) Oldest.oldhamite(mineralogy) The mineral form of calcium sulphide.oldschoolAlternative form of old school.oldstylesplural of oldstyleoldtimersplural of oldtimeroleaceousOf or relating to the plant family Oleaceae.oleacinid(zoology) Any snail in the family Oleacinidae.oleagenin(organic chemistry) The aglycone of various oleasides.oleandersplural of oleanderoleandrin(chemistry) One of several glycosides found in the leaves of the oleander plant.oleanolicOf or pertaining to oleanolic acid or its derivativesoleanonicOf or pertaining to oleanonic acid or its derivativesoleclumabA human monoclonal antibody used to treat certain cancersolecranal(anatomy) Of or pertaining to the olecranon.olecranon(anatomy) The bony process at the top of the ulna forming the point of the elbow.olecrononMisspelling of olecranon.oleiferinAny of a group of antifungal lignans present in Virola oleiferaolenellid(zoology) Any trilobite in the family Olenellidae.oleogenicRelating to oleogenesisoleograph(art) A type of chromolithograph, using oil paint on canvas, that attempts to imitate oil paintingoleolysisThe separation of a layer of oil from a mixtureoleolyticRelating to, or causing oleolysisoleomancy(divination, historical) The practice of divination by pouring oil into water and observing the resulting patterns.oleometer(chemistry) An instrument for determining the weight and purity of oil.oleoptene(chemistry) Alternative form of elaeoptene.oleoresinA homogeneous mix of essential oil and resin.olfactantSynonym of odorant.olfacticsThe study of smells and how they are perceived.olfactionThe sense of smell; the detection of airborne molecules.olfactiveOf or pertaining to the sense of smell; olfactoryolfactome(biology) All the olfactory compounds used by a particular organismolfactory(relational) Concerning the sense of smell.oligaemia(medicine) The condition of having a low quantity of blood.oligaemicRelating to or exhibiting oligaemia.oligandry(botany) The state of being oligandrous.oligarchsplural of oligarcholigarchyA government run by and for only a few, often the aristocracy, the wealthy, or their friends and associates.oligistic(mineralogy, archaic) Of or relating to oligist, or hematite.oligoagarAny oligosaccharide present in agaroligobody(immunology) A complex of an aptamer and an antibodyoligoconeHaving a reduced number of functioning cone cells.oligodiol(organic chemistry) Synonym of oligoether.oligogene(genetics) One of a few genes that, together, control a specific traitoligogynyThe situation where an ant colony has multiple egg-laying queens, but they remain far apart from one another in the nest.oligolegeA pollinator exhibiting oligolecty.oligomersplural of oligomeroligomeryThe condition of being oligomeric.oligopneashallow breathingoligopoly(economics) An economic condition in which a small number of sellers exert control over the market of a commodity.oligosemy(linguistics, especially of a term whose range of meanings has been semotactically restricted) The quality or state of having a few meanings, as opposed to having a single meaning or many meanings.oligosomeA nucleosome oligomeroligotype(genetics, taxonomy) A distinct taxon whose separate identity is derived from a string of genetic bases rather than from morphological differencesoligourea(organic chemistry) Any compound containing several urea moietiesoligouria(pathology) A condition in which only a relatively small amount of urine (typically about 400ml per day) is producedoliphaunt(archaic and historical) elephantolivacineA particular antimalarial alkaloid.olivaster(archaic, uncommon) Of the color of the olive; tawny.olivebackAny of the birds in the genus Nesocharis or Delacourella, found in western and central Africa.olivelessWithout olives.olivelikeResembling or characteristic of an olive.olivellid(zoology) Any sea snail in the family Olivellidae, now considered to be part of the family Olividae.olivenessThe state or condition of being olive in colour.olivenite(mineralogy) An orthorhombic copper arsenate mineral with the chemical formula Cu₂AsO₄OH.olivewoodThe wood of the olive treeolivinite(mineralogy) duniteollycrock(South Africa) giant periwinkleolmutinibThe antineoplastic drug N-[3-[2-[4-(4-methylpiperazin-1-yl)anilino]thieno[3,2-d]pyrimidin-4-yl]oxyphenyl]prop-2-enamideololiuquiAlternative form of ololiuhqui.olprinone(pharmacology) A particular kind of cardiotonic agent.olusatrum(archaic) An umbelliferous plant, the common alexanders, found in Western Europe (Smyrnium olusatrum).olympiadsplural of olympiadombrophilAlternative form of ombrophile.ombrotypeA type of climate that has a certain amount of rainfallombudsmanAn appointed official whose duty is to investigate complaints, generally on behalf of individuals such as consumers or taxpayers, against institutions such as companies and government departments.ombudsmenplural of ombudsmanomegaball(sports) A variant of soccer (“association football”), played on a round pitch with more than two teams, and associated goals.omegaformIn the shape of the letter omega.omegasomeA cup-shaped protrusion from the endoplasmic reticulum that serves as a platform for autophagosome biogenesis in mammalian cells.omegatronA kind of mass spectrometer using the principles of cyclotron acceleration.omelettesplural of omeletteomeletteyAlternative form of omeletty.omenologyThe study of omens.omentallyIn an omental manneromentitisinflammation of the omentumomethoateA systemic organophosphorous insecticide and acaricide used in horticulture and agriculture.omination(obsolete) presage; omen.ominelite(mineralogy) An orthorhombic-dipyramidal blue mineral containing aluminum, boron, iron, magnesium, oxygen, and silicon.ominosityThe state or quality of being ominous.ominouslyIn an ominous manner; with sinister foreboding.omissibleAble to be omitted.omissionsplural of omissionomittableSynonym of omissible.omittanceThe act of omitting something; omission.ommatidiaplural of ommatidiumommissionMisspelling of omission.omnibusesplural of omnibusomnicidalOf or relating to omnicide.omnigenic(genetics) Concerning, or controlled by, all the genes of an organismomnipauseA type of neuron that has a role in the stability of the saccadic systemomnipolarOperating with either (north or south) magnetic poleomnipowerSynonym of hyperpower (“international hegemon”).omnirange(aviation, chiefly attributive) A short-range radio navigation system for aircraft, based on a network of fixed radio beacons on the ground.omniscentMisspelling of omniscient.omnitonic(music, of an instrument) That can be played in any key.omniverse(science fiction) The entire set of co-existing universes, multiverses, etc.omnivoresplural of omnivoreomniwheelAlternative form of omni wheel.omophagiaThe eating of raw food, especially raw flesh.omophagicEating raw flesh; using uncooked meat as food.omophoriaplural of omophorionomphacine(obsolete) Made from unripe olives.omphacite(mineralogy) Any of a range of green, monoclinic pyroxene minerals found in eclogites and similar rocks; they are solid solutions of jadeite and diopside.omphalismA tendency to place the capital of a country at its geographical centre, or to increase the powers of central government at the expense of local government.omphalode(botany, obsolete) The central part of the hilum of a seed, through which the nutrient vessels pass into the raphe or chalaza.omphaloidShaped like a navel.omuralideA transformation product of lactacystin.onanisticOf or pertaining to masturbation (onanism).onchidiid(zoology) Any slug in the family Onchidiidae.oncocyticOf or pertaining to an oncocyte or to oncocytomaoncofetalTypically present only during fetal development, but also found in adults with certain cancers.oncogenesplural of oncogeneoncogenicCausing the formation of tumors.oncographAn instrument for registering the changes observable with an oncometer.oncolipidAny lipid that is associated with a canceroncoliticContaining oncoids or pertaining to oncolite.oncologic(oncology) Of or pertaining to oncologyoncolysisThe breakdown or destruction of a tumour.oncolyticThat breaks up cancer cells.oncometer(physiology) An instrument for measuring the variations in size of the internal organs of the body.oncomouseA type of laboratory mouse that has been genetically modified to carry an activated oncogene, increasing its susceptibility to cancer.oncopodid(zoology) Any harvestman/daddy longlegs in the family Oncopodidae, a synonym of the Sandokanidae.oncostainA substance that stains cancerous tissue (in microscopic examination)oncostman(mining, historical) Any workman who was paid a daily rate.oncoviralRelating to an oncovirusoncovirusA virus that can cause cancer.ondioline(music) An early type of synthesizerondographAn instrument for autographically recording the waveforms of varying currents, especially rapidly varying alternating currents.ondometerAn instrument designed to measure wavelengths.ondoscope(physics) An instrument that detects (and visualizes) the presence of high-frequency radiationonehandedAlternative form of one-handed.oneillite(mineralogy) A trigonal-pyramidal yellowish brown mineral containing calcium, chlorine, hydrogen, iron, manganese, niobium, oxygen, silicon, sodium, and zirconium.oneirodid(zoology) Any fish of the family Oneirodidae.oneirogenAny drug, herb, etc. that produces or enhances a dream-like state of consciousness.oneirosisA form of light hypnosis.oneiroticOf or relating to oneirosis.onelinersplural of onelineroneliness(obsolete) The state of being one or single.oneration(obsolete) The act of loading or burdening.onerosity(Scots law) The legal state of affairs resulting from being done or given in return for receipt of something of value.onerouslyIn an onerous manner.onflowingflowing onwardonforward(transitive) To forward (resend).ongoinglyIn an ongoing fashion.onholdingContinuous; perpetual; lasting.onigirazuA form of sushi having the filling sandwiched between portions of rice instead of formed into a circle.oniomania(psychology) An abnormal impulse to buy things, or a condition characterised by such impulses.onionized(informal, rare) Flavoured with, or converted into, onion; made oniony.onionlessWithout onions.onionlikeResembling or characteristic of an onion, for example in shape, flavour, or layered structure.onionskinA thin, strong, light, translucent paper; used especially for making carbon copies.onionweedAsphodelus fistulosus, an annual or short-lived perennial herb with a hollow stem and a large tuft of onion-like rounded hollow leaves.onlookersplural of onlookeronlookingThat is looking on; watching, observing.onomanticOf or relating to onomancy.onomasticOf or relating to a personal or place name.onomatoid(philosophy) In the philosophy of reism, any name denoting a state, relation, property, etc. rather than a body.onomatope(linguistics) A word formed by onomatopoeia or mimesis.onomatopyAlternative form of onomatopoeia.onopordum(botany) Any of the genus Onopordum of asteraceous thistles.onrushingrushing or flowing forwardonsettingpresent participle and gerund of onsetonslaughtA fierce attack.onticallyIn an ontic sense.ontogenicSynonym of ontogeneticontosophy(philosophy) A comprehensive explanation for being (in contrast to merely a description of being, or a reason for being).onychinus(obsolete) onyxonychitisSynonym of onychia.onychopodAny branchiopod crustacean of the suborder Onychopodaonychosis(pathology) Any disease or disorder of the fingernails or toenails.onymously(rare) In an onymous manner; having a name.ooblasticRelating to the ooblast.oodiaulic(biology) Having two reproductive duct systems, a hermaphroditic one for copulation and one for depositing eggs.oogenesesplural of oogenesisoogenesis(biology) The formation and development of an oocyte or ovumoogeneticOf or pertaining to oogenesis.oogenotop(zoology) The egg-forming apparatus in trematodes.oogoniumsplural of oogoniumookinetic(biology) Tending to produce the female element.oolacuntaAn extinct marsupial, the desert rat kangaroo (Caloprymnus campestris), that lived in a sand-ridge and gibber-plain habitat in south-western Queensland and north-eastern Australia.oologicalOf or relating to oology.oompahpahAlternative spelling of oom-pah-pah.oomphlessLacking oomph (vitality or sex appeal).oomycetesplural of oomyceteoophagousRelating to or exhibiting oophagy.oophoromaA tumor of the ovary.oophorousContaining eggs or ova.ooplasmicConcerning the cytoplasm of eggsoorhodein(archaic) A reddish-brown pigment found in eggshells.oospecies(taxonomy) An ootaxon, equivalent to a species, used to classify fossilised dinosaur eggsoospheresplural of oosphereoosporein(organic chemistry) A dibenzoquinone that is a toxic metabolite of the fungus Cochliobolus kusanoioostegite(zoology) One of the plates which, in some crustaceans, enclose a cavity in which the eggs are hatched.opacatingpresent participle and gerund of opacateopacifiedsimple past and past participle of opacifyopacifier(chemistry) a chemical agent added to a material, such as rocket propellant, to make it opaqueopacitiesplural of opacityopakapakaPristipomoides filamentosus, the crimson jobfish.opalesqueSimilar to opal; having some of the qualities of opal.opalizingpresent participle and gerund of opalizeopalotype(historical, photography) A photograph taken on opalescent glass.opensider(rugby) openside flankeroperagoerSomeone who attends an opera performanceoperalikeResembling or characteristic of opera.operantlyIn an operant manneroperaticsexaggerated or overly emotional behaviour; histrionicsoperatingIn operation; that operates.operation(uncountable) The method by which a device performs its function.operatiseAlternative form of operatize.operatistA composer of opera.operativeEffectual or important.operatize(transitive) To convert into operatic form.operatorsplural of operatoroperatoryOf or relating to operations.operatourObsolete form of operator.operatrix(dated) A female operator.opercular(anatomy, botany, zoology) relating to the operculumoperculum(zoology) A covering flap in animals, such as a gill cover.operettasplural of operettaoperetticof or relating to an operettaoperidine(pharmacology) The opioid analgesic drug pethidine.operoselyIn an operose manner.operosityLaboriousness; painstakingness.ophiactid(zoology) Any brittle star in the family Ophiactidae.ophidiansplural of ophidianophidioid(zoology) Any of the family Ophidiidae of cusk-eels.ophidiousArchaic form of ophidian.ophiolite(geology) An assemblage of mafic and ultramafic rock fragments of the ocean lithosphere that has been tectonically moved onto a continental margin or island.ophiology(zoology) The study of snakes, a branch of herpetology.ophiopsidAny extinct fish of the family OphiopsidaeophiruoidMisspelling of ophiuroid.ophiuroidAn echinoderm of the class Ophiuroidea; the brittlestar.ophthalmyArchaic form of ophthalmia.opicaponeA drug for the treatment of Parkinson's disease.opiferous(rare) Bringing help; helpful.opilionid(zoology) Any of the harvestmen/daddy longlegs in the order Opiliones.opinationThe state or process of opining.opinativeConjectural; expressing an opinion rather than a fact.opiniatedObsolete form of opinionated.opiniator(obsolete) Someone who is opinionated.opiniatreObsolete form of opiniaster.opinional(rare) Based on or constituting an opinion.opinionedsimple past and past participle of opinionopiomaniaOpium addiction.opiophileA person who enjoys taking opium.opiorphin(biochemistry) A painkilling chemical compound first isolated from human saliva.opiparous(obsolete) Sumptuous, luxurious.opipramolA psychoactive drug used as an anxiolytic and antidepressant.opisthion(anatomy) The middle of the posterior margin of the foramen magnum of the skull.opiumlikeResembling or characteristic of opium.opobalsam(medicine, obsolete) The aromatic resinous juice of Commiphora opobalsamum (balm of Gilead).opodeldoc(obsolete) A kind of plaster, said to have been invented by Mindererus, used for external injuries.opopponaxAlternative form of opopanax.opostegid(zoology) Any moth in the family Opostegidae.oppletion(obsolete) The act of filling up.opponency(UK) The act of opening an academic disputation; the proposition of objections to a tenet, as an exercise for a degree.opponentsplural of opponentopportuneSuitable for some particular purpose.opposableSusceptible to being opposed or resisted.opposablyin an opposable manneropposedlyIn an opposed manneroppositesplural of oppositeoppressedSubject to oppression.oppresseeA victim of oppression.oppressesplural of oppressoppressorSomeone who oppresses another or others.opprobrieObsolete spelling of opprobry.oppugnantopposing, antagonistic, contraryoprichnik(historical) A member of the bodyguard corps established by Tsar Ivan the Terrible to govern a division of Russia from 1565 to 1572.oprodioneA particular fungicide.opsimathsplural of opsimathopsimathyLearning or education that occurs late in life.opsomania(medicine, dated) A longing for a particular special food.opsonisesthird-person singular simple present indicative of opsoniseopsonizedsimple past and past participle of opsonizeopthalmicMisspelling of ophthalmic.opticallyregarding or using opticsopticiansplural of opticianoptigraphA telescope with a diagonal eyepiece, suspended vertically in gimbals by the object end beneath a fixed diagonal plane mirror. It is used for delineating landscapes by means of an attached pencil.optimallyIn an optimal manner.optimatesplural of optimateoptimedin(biochemistry) A particular olfactomedinoptimeterA form of interferometer used in the measurement of gauge blocks.optimific(philosophy) producing the optimum outcomeoptimisedsimple past and past participle of optimiseoptimiserAlternative spelling of optimizer.optimisesthird-person singular simple present indicative of optimiseoptimistsplural of optimistoptimizedsimple past and past participle of optimizeoptimizerA person in a large business whose task is to maximize profits and make the business more efficient.optimizesthird-person singular simple present indicative of optimizeoptionary(dated) optionaloptocoele(anatomy) The cavity of one of the optic lobes of the brain in many animals.optoejectTo optically ejectoptometerAn instrument for measuring the focus of the lens of the eye.optometryThe art and science of vision and eye care.optomotorDescribing movement of the eye, head or body (especially of insects) that steadies the field of visionoptophoneA device that transforms light into sound.optotypicRelating to an optotypeoptronicsoptoelectronicsopulencesplural of opulenceopulentlyIn an opulent manner.opuntioidAny cactus of the subfamily OpuntioideaeopusculumAn opuscule; a short work.oraculous(now rare) Oracular.oralisticOf or pertaining to oralism.oralitiesplural of oralityoralnasal(rare) oronasalorangeadeA soft drink or a soda with an orange flavor.orangeishAlternative spelling of orangish.orangeite(mineralogy) A kind of kimberlite with phlogopite macrocrysts and microphenocrysts.orangerieAlternative form of orangery.orangetipAlternative spelling of orange tip.orangutanAn arboreal ape, characterised by their shaggy reddish-brown coat and long arms, which comprise the genus Pongo, native to Borneo and Sumatra.oratoressAlternative form of oratress.oratorial(rare) oratorical.oratorianA member of a Roman Catholic oratory.oratoriesplural of oratoryoratoriosplural of oratoriooratorize(humorous or derogatory) To play the orator.orazamideA synthetic hepatoprotective drug.orbicularCircular or spherical in shape; round.orbispace(mathematics) A topological space or generalization of an orbifold.orbitalis(anatomy) A muscle that controls protrusion of the eyeball.orbitally(sciences) By means of or in relation to orbitorbituary(archaic) orbitalorbiviralRelating to orbivirusesorbivirusAny virus of the genus Orbivirus, many of which are carried by ticksorbofiban(pharmacology) An orally active platelet receptor antagonist.orbuculum(paganism) A crystal ball.orbweaverAny spider of the family Araneidae.orcharderOne who owns or operates an orchard.orchester(US, nonstandard or dialect) An orchestra.orchesticRelating to danceorchestra(Ancient Greece, theater) A semicircular space in front of the stage used by the chorus in Ancient Greek and Hellenistic theatres.orchestreObsolete form of orchestra.orchidean(botany) orchidaceousorchidistA person who cultivates orchids.orchidoidAny orchid belonging to the subfamily Orchidoideae.orchotomy(dated) The surgical removal of a testicle; castration.orcokininAny of a family of crustacean peptides that elicit potent myotropic effects in gut tissuesordainersplural of ordainerordainingpresent participle and gerund of ordainorderableThat may be ordered (obtained by placing an order).orderingsplural of orderingorderlessDevoid of order or arrangement; chaotic.orderliesplural of orderlyordertypeAlternative form of order type.ordinable(obsolete) ordainable.ordinaireWine for ordinary use.ordinallyIn an ordinal manner.ordinance(US) A local law, passed by e.g. a city.ordinatedsimple past and past participle of ordinateordinatesplural of ordinateordinatorOne who ordains or establishes; a director.ordnancesplural of ordnanceordonnantOf or relating to ordonnance.orebodiesplural of orebodyoregonite(mineralogy) A hexagonal nickel iron arsenide mineral.oreibasiaA nocturnal ceremony of Bacchic women in Ancient Greece.orellanin(organic chemistry) orellanineoreoselin(organic chemistry) A white crystalline substance which is obtained indirectly from the root of an umbelliferous plant, Oreoselinum majus (formerly Imperatoria oreoselinum), and yields resorcin on decomposition.orestrate(pharmacology) A synthetic steroidal estrogen, the 3-propanoyl, 17-(1-cyclohexenyl) ether of estradiol.organbirdThe pied butcherbird (Cracticus nigrogularis).organdiesplural of organdyorganellaSynonym of organelle.organelle(cytology) A specialized structure found inside cells that carries out a specific life process (e.g. ribosomes, vacuoles).organetteAn early mechanical accordion that played music encoded on rolls of perforated paper.organicalArchaic form of organic.organificMaking an organic or organized structure; producing an organism.organisedsimple past and past participle of organiseorganiserNon-Oxford British English standard spelling of organizer.organisesthird-person singular simple present indicative of organiseorganismsplural of organismorganista(archaic) Any of several South American wrens of the order Troglodytidae, noted for the sweetness of their song.organistsplural of organistorganized(of things or settings) Having been organized; in good order.organizerA person who arranges the details of a public event.organizesthird-person singular simple present indicative of organizeorganlessWithout organsorganlike(biology) Having characteristics of an organ.organogelA liquid organic phase containing a three-dimensional cross-linked networkorganogen(chemistry, dated) Any of certain other elements sometimes found in organic compounds, such as sulphur and phosphorus.organoidsplural of organoidorganonicPertaining to an organon.organosolA histosol, a soil comprising chiefly organic material.organotin(organic chemistry) Describing any organic compound containing a carbon to tin bondorganular(biology) Of or pertaining to an organ of the body.organwide(biology) Throughout an organ.organzine(archaic) A kind of double thrown silk of very fine texture; silk twisted like a rope with different strands, so as to increase its strength.orgasmingpresent participle and gerund of orgasmorgiasticRelating to an orgy; uncontrolled, wild.orgillous(literary, archaic) Alternative spelling of orgulous (“arrogant, haughty, proud”)orgonomicRelating to orgonomy.oricalcheObsolete form of orichalchum.orichalchAlternative form of orichalcum.orientalsplural of orientalorientate(UK, Ireland, Commonwealth, intransitive) To face a given direction.orienteer(sports) Someone who takes part in the sport of orienteering.orientingpresent participle and gerund of orientorientite(mineralogy) An orthorhombic-dipyramidal mineral containing calcium, hydrogen, manganese, oxygen, and silicon.orifacialAlternative form of orofacial.orificial(medicine) Of or relating to the orifices of the body.oriflamme(figuratively) Any banner, idea or principle which serves as a rallying point for those involved in a struggle.origamistA person who does origami.originallObsolete spelling of original.originalsplural of originaloriginant(archaic) originaloriginary(rare) Pertaining to or being the origin of something.originate(intransitive) To come into existence; to have origin or beginning; to spring, be derived (from, with).oripavine(organic chemistry) An opiate alkaloid 6,7,8,14-tetradehydro-4,5α-epoxy-6-methoxy-17-methylmorphinan-3-ol that is a metabolite of thebaineornamentsplural of ornamentorneriestsuperlative form of ornery: most orneryornithine(biochemistry, organic chemistry) An amino acid, 2,5-diaminopentanoic acid, that is not present in protein, but is an intermediate in the biosynthesis of urea.ornithoidResembling or characteristic of a bird.oroantralRelating to the oral and antral cavities.oroblancoA hybrid fruit developed by crossing a pomelo and a white grapefruit. When fully developed, it is approximately the size of a grapefruit.orobuccal(anatomy) Relating to the mouth and the cheekoroclinalRelating to an orocline.orodental(anatomy) Relating to the mouth and the teethorodontid(zoology) Any extinct cartilaginous fish in the family Orodontidae.orofacial(anatomy) Of or affecting both the mouth and face.orofaecalAlternative form of orofecal.orogeniesplural of orogenyorogenous(geology) Of or relating to mountain-building; orogenic.orography(geomorphology) The scientific study, or a physical description of mountains.orolabialRelating to the mouth and lips.orolarynx(anatomy) The oral part of the larynxorologist(obsolete, rare) an expert in orology.oromanualRelating to the mouth and the handsoroselone(organic chemistry) The furanocoumarin 8-prop-1-en-2-ylfuro[2,3-h]chromen-2-one present in angelicaorosphereA clump of oral cancer cellsorotidine(biochemistry) A nucleoside formed by reaction of orotic acid with riboseorotomideAny of a particular class of antifungal agentsorotundlyIn an orotund manner.orphalineObsolete form of orpheline.orphanageA residential institution for the care and protection of orphans.orphandomThe state of being an orphan.orphaningpresent participle and gerund of orphanorphaniseNon-Oxford British English standard spelling of orphanize.orphanishResembling or characteristic of an orphan.orphanismThe state of being an orphan.orphanity(rare) The state of being an orphan; orphanhood.orphanize(transitive, archaic) To orphan.orpharion(music) A musical instrument of the Renaissance, part of the cittern family, whose metal strings are tuned like a lute's and plucked with the fingers.orpheline(obsolete) An orphan.orpherionAlternative form of orpharion.orrisrootThe root of the orris.orsellate(organic chemistry) Any salt or ester of orsellic acid.orsolobid(zoology) Any spider in the family Orsolobidae.ortaniqueA cross between an orange and a tangerine.ortataxelA particular drug used in chemotherapy.orteronelA non-steroidal antiandrogen that was investigated as a cancer treatment but later dropped.orthaxialthat has a straight vertebral axisorthenineA particular steroid glycoside.ortheziid(zoology) Any scale insect of the family Ortheziidae.orthiconsplural of orthiconorthoacid(inorganic chemistry) the member of a series of oxyacids of a particular element that has the highest number of hydroxyl groupsorthocladAny midge of the chironomid subfamily Orthocladiinaeorthocone(malacology) A long straight shell of a nautiloid cephalopod.orthodataConstraints or assessments applied to transactional or warehoused data to assure data quality.orthodome(crystallography) A dome that is parallel to the orthodiagonal in a monoclinic crystal.orthodoxyCorrectness of doctrine and belief in regard to any doctrinal (i.e. philosophical or theological) system.orthoepicOf or relating to orthoepy in its various senses:orthoform(dated) A former anaesthetic.orthogamy(botany) fertilization of the ovules of a plant by pollen from the same plantorthogridA structure similar to an isogrid but having rectangular rather than triangular openings.orthologyCorrect speaking or the correct use of words.orthomode(physics, attributive) describing a transducer that use two orthogonally polarized microwave beamsorthopair(mathematics) A pair of orthogonal or disjoint subsets (of a given universe)orthopedyArchaic form of orthopedics.orthoplex(geometry) A convex polytope analogous to an octahedron (3 dimensions) or 16-cell (4 dimensions).orthopneaAlternative spelling of orthopnoea.orthopnicExhibiting or relating to orthopnoea.orthopraxCorrect in practice (though not necessarily in opinion or belief); practically right, doing the right actions.orthopterAny insect of the order OrthopteraorthopticRelating to orthoptics, the study and treatment of muscular irregularities of the eye.orthostat(archaeology) An upright stone or slab, especially one which is part of a larger structure.orthotics(medicine) The design, manufacture and installation of orthopedic appliances to support, straighten or improve the function of a body partorthotistA person who makes or fits orthotic devices.orthotomy(geometry) The property of cutting at right angles.orthotone(grammar) An orthotone form.orthotope(geometry) The generalization of a rectangle for higher dimensions, formally defined as the Cartesian product of intervals.orthotype(taxonomy) The original published name for a group of genetically related organisms.ortologueMisspelling of orthologue.orzavirusMisspelling of oryzavirus.osanetant(pharmacology) A neurokinin 3 receptor antagonist being researched for the treatment of schizophrenia.osaterone(pharmacology) A particular antiandrogen.osbornite(mineralogy) A golden yellow mineral containing nitrogen and titanium.oscillate(intransitive) To swing back and forth, especially if with a regular rhythm.oscitancythe act of yawningosculance(Bantu linguistics) The state of being osculant.osculatedsimple past and past participle of osculateosculatesthird-person singular simple present indicative of osculateosculator(Vedic arithmetic) An algorithm for performing osculation.oshidashi(sumo) a kimarite in which the attacker pushes his opponent out of the ring, maintaining hand contact at all timesoshizushisushi made in compressed block form and then cut into piecesosierlikeResembling or characteristic of an osier.osmanthusAny of several widely distributed evergreen flowering plants, of the genus Osmanthus.osmeteriaplural of osmeteriumosmiamate(obsolete, chemistry) A salt of osmiamic acid.osmoadaptTo undergo osmoadaptation.osmographAn instrument for recording the height of the liquid in an endosmometer or for registering osmotic pressures.osmolysedBroken down by osmolysisosmolysisThe rupture of a cell wall due to excessive osmotic pressureosmolyticRelating to osmolysisosmometerAny of various devices used to measure osmotic pressure.osmometry(physics, chemistry) The measurement of osmotic pressureosmophile(biology) Any organism that is adapted to living in aqueous environments with high solute concentrations (salt, sugar, alcohol), and resisting internal desiccation caused by the osmotic transport of water outside of their cellsosmophily(microbiology) The quality of growing well under high osmotic pressure.osmophore(chemistry) An osmophoric grouping of atoms in a moleculeosmoscopeAn instrument for detecting and for measuring odors.osmoshockosmotoxic shockosmotaxis(biology) movement of an organism in an osmotic pressure gradientosmoticum(biology) Any substance that acts to supplement osmotic pressure in a cellosmotoxicRelating to osmotoxicityosmotrophAny osmotrophic organismosmundine(botany) The roots of ferns of the genus Osmunda, used in growing orchids etc.osotogari(judo) A throw in which (right-handed version) tori steps next to uke with his left leg and reaps uke's right leg (at the back of the thigh) with his right leg.ossamycinA particular cytotoxic agent.osseouslyBy means of bone.ossiconedHaving one or more ossiconesossicular(anatomy) Related to or composed of ossicles.ossiculum(anatomy) An ossicle.ossifragaAlternative form of ossifrage.ossifrage(British) The osprey.ossifyingpresent participle and gerund of ossifyossiphagy(biology) Feeding on bones.ossuariesplural of ossuaryossuariumA charnel house; an ossuary.ostealgia(pathology) Pain coming from one's bone(s).ostectomy(surgery) Excision of all or part of a bone.ostension(philosophy) The act of presenting an ostensive definition.ostensiveApparently true, but not necessarily; ostensibleostensoirSynonym of monstrance.ostentate(transitive, rare) To make an ambitious display of; to exhibit or show boastingly.ostentive(linguistics) Used to indicate or draw attention to something specific.ostentous(obsolete) ostentatiousosteocope(medicine, archaic) pain in the bonesosteocrin(biochemistry) A peptide that contributes to osteogenesis and chondrogenesis in some fishosteocyte(cytology) A mature bone cell involved with the maintenance of bone.osteoderm(anatomy) A bony deposit in the dermal layers of the skinosteogenyosteogenesisosteokine(biochemistry) A form of cytokine produced in bone cells.osteolite(mineralogy) A massive impure apatite, or calcium phosphate.osteolithA mass of bone tissue (in an inappropriate place)osteology(anatomy) The scientific study of the morphology and pathology of bones.osteomataplural of osteomaosteopath(alternative medicine) A non-physician healthcare practitioner who practices osteopathy by manipulating the skeleton and muscles. Not to be confused with Doctors of Osteopathic Medicine (D.O.) (also known as osteopathic physicians) who are full physicians like Doctors of Medicine (M.D.).osteotomeA medical tool used for cutting or marking bone, used in dental implantation.osteotomy(surgery) The surgical procedure of cutting a bone. This is often performed to either lengthen, shorten, or straighten a bone.ostiariesplural of ostiaryostiarius(Winchester College) A student office held by a prefect with the duties of keeping order, collecting the vulguses, and ensuring the other students attend class.ostinatosplural of ostinatoostiolateHaving an ostiole.ostleressA female ostler.ostracean(zoology, archaic) Any bivalve of the family Ostreidae; an oyster.ostraciid(zoology) Any fish in the family the Ostraciidae.ostraciseNon-Oxford British English standard spelling of ostracize.ostracism(figuratively) Banishment by some general consent.ostracite(paleontology, archaic) A fossil oyster.ostracize(transitive, Ancient Greece, historical) To ban a person from a city for five or ten years through the procedure of ostracism.ostracodeAlternative form of ostracod.ostracodsplural of ostracodostracoid(zoology, obsolete) Of or pertaining to the ostracodsostrasizeMisspelling of ostracize.ostrichesplural of ostrichostricizeMisspelling of ostracize.ostringerObsolete form of austringer.ostrisizeMisspelling of ostracize.ostruthin(organic chemistry) An organic compound found in the masterwort (Imperatoria ostruthium).ostruthol(organic chemistry) A coumarin found in the plant Angelica archangelica.osumiliteA hexagonal mineral with the chemical formula (K,Na)(Mg,Fe⁺²)₂(Al,Fe)₃(Si,Al)₁₂O₃₀·H₂O.otherable(rare) Capable of being othered.otherhoodThe state or quality of being other.otherlingOne who is different from others; someone or something possessing unique qualities; an exception; dissident.otherness(uncountable) The quality of being different or distinct.othersome(now dialectal or poetic) Some others.otherwardToward an other.otherwaysOtherwise; by another means; in other respectsotherwhen(rare) Other time (sometime else).otherwise(manner) Differently, in another way.otherwizeMisspelling of otherwise.otiatricsThe study of diseases of the ear and their treatment.otoconialOf or pertaining to an otoconium.otoconite(anatomy) A mass of otoliths.otoconium(anatomy, medicine) Synonym of otolith.otocysticRelating to the otocyst.otodontid(zoology) Any in the family Otodontidae of extinct sharks.otoferlin(biochemistry) A transmembrane protein which is defective in a recessive form of human deafnessotographyThe scientific description of the ear.otokonoko(Internet slang) A male who has extremely feminine appearance and mannerisms.otolithicOf or pertaining to an otolith.otologistA doctor specializing in otology.otometricOf or pertaining to otometry.otonality(music) A family of pitches that can all be expressed as ratios with a specified fixed tone, such that all ratios have the same denominator.otonecine(organic chemistry) A pyrrolizidine alkaloid.otopathicRelating to otopathy.otopetrin(biochemistry) Any of a group of transmembrane proteins associated with otoconia and with sensing the sour tasteotophysan(zoology) Any of the fish of the Otophysi series within the Ostariophysi superorder, also known as the Otophysa in some classifications.otophysic(ichthyology) Of or pertaining to a connection between the swim bladder and inner ear in certain species of fish.otoplasty(surgery) A procedure of plastic surgery used to change the appearance or shape of a person’s ears.otorrhoea(chiefly British spelling) Alternative form of otorrhea.otoscopesplural of otoscopeotoscopicrelating to otoscopy or otoscopesotosenine(organic chemistry) An alkaloid found in ragwort (Jacobaea vulgaris, syn. Senecio jacobaea).otosphereA spherical collection of cochlear epithelial cellsotterlessWithout otters.otterlikeResembling or characteristic of an otter (animal).ottermode(slang, bodybuilding, often attributive) A lean and physically-fit physique with well-defined muscles.otterskinThe pelt of an otter.ottrelite(mineralogy) A form of the mineral chloritoid.ouanderooArchaic form of wanderoo.oublietteA dungeon only accessible by a trapdoor at the top.oughtness(chiefly philosophy) In ethics, the quality which makes an action dutiful or morally obligatory.ounceland(historical, Scotland) An old Scots unit of measure equal to 20 pennylands.ouroboricSelf-referring, self-reflexive, self-consuming; recursiveouroboros(mythology) A serpent, dragon or worm that eats its own tail, a representation of the continuous cycle of life and death.ouroscopyObsolete form of uroscopy.ourselves(reflexive) Us; the group including the speaker as the object of a verb or preposition when that group also is the subject.oursinite(mineralogy) An orthorhombic pale yellow mineral containing cobalt, hydrogen, magnesium, oxygen, silicon, and uranium.outambush(transitive) To surpass in ambushing.outasight(slang, dated) excellent, amazingoutbabbleTo babble excessively.outbackerOne who lives in the outback.outbanderSynonym of freebander.outbasketA basket holding documents or mail to be sent to others; an outbox.outbattle(transitive) To overcome in battle.outbellow(transitive) To bellow louder or longer than.outbidderOne who outbids.outborrowTo borrow more than.outboundsplural of outboundoutboxingpresent participle and gerund of outboxoutbranchA branch of a tree, bush, or shrub that extends outward; offshoot.outbravedsimple past and past participle of outbraveoutbravesthird-person singular simple present indicative of outbraveoutbrazen(transitive) To bear down with a brazen face.outbreaksplural of outbreakoutbreast(poetic, transitive) To surpass in singing; to sing better than.outbreathA breath given out; an exhalation.outbreedsthird-person singular simple present indicative of outbreedoutburstsplural of outburstoutbustle(transitive) To surpass in bustling; to be more busily energetic than.outcastedsimple past and past participle of outcasteoutcharge(transitive, sports) To surpass in charging, or moving forcefully forward.outclamor(transitive) To make more noise than.outcomingThat comes out.outcouple(physics) To remove the coupling between two interacting beams of laser lightoutcrafty(transitive) To exceed in craft or cunning; overpower by guile.outcryingpresent participle and gerund of outcryoutcurvedThat curves outwardsoutdaringpresent participle and gerund of outdareoutdazzle(transitive) To surpass by dazzling more than; to outshine.outdebate(transitive) To surpass in debating.outdegree(graph theory) The number of edges directed out of a vertex in a directed graph.outdesign(transitive) To surpass in design; to design better than.outdirect(transitive, nonce word) To surpass in directing.outdooredsimple past and past participle of outdooroutdoorsy(informal) Associated with the outdoors, or suited to outdoor life.outendure(transitive) To endure beyond; to outlast.outercoatA topcoat or overcoat.outermostsuperlative form of outer: most outer; farthest outside; as far from the center or inside as possible.outernessThe quality of being outer.outerside(dated) An outward side; outside surface.outerwearClothing (such as a dress) worn over one's underwear.outfanned(poetic) fanned outoutfieldsplural of outfieldoutfightsthird-person singular simple present indicative of outfightoutfigure(transitive) To outthink.outfinish(transitive) To finish ahead of; to defeat or surpass by finishing first.outfittedsimple past and past participle of outfitoutfitterA person or shop that sells specialized clothes and equipment.outflightThe act or process of flying out.outfoughtsimple past and past participle of outfightoutfoxingpresent participle and gerund of outfoxoutfriend(transitive) To befriend or gain more friends than (another)outfumble(transitive) To surpass in fumbling.outgabble(transitive) To surpass in gabbling or chattering.outgallop(transitive, especially of horses or riders) To run faster than; to outdistance.outgamble(transitive) To surpass in gambling; to gamble more or better than.outgassedsimple past and past participle of outgasoutgivingpresent participle and gerund of outgiveoutgoingsplural of outgoingoutgroundGround situated at a distance from the house; outlying land.outgroupsplural of outgroupoutgrower(chiefly Africa) A farmer who undertakes to supply a buyer with crops or livestock at some future time and meeting certain requirements; in return, the buyer agrees to make the purchase (perhaps at a pre-agreed price) and may provide other support.outgrowthAnything that grows out of something else.outguardsplural of outguardoutgunnedpast participle of outgunouthammer(transitive) To hammer more or harder than.outhandle(transitive) To surpass in handling.outharborAlternative spelling of outharbour.outhasten(transitive) To be faster than.outhaulerSynonym of outhaul.outhorror(transitive, rare) To surpass in horror; to be more horrifying than.outhousesplural of outhouseouthumourAlternative form of outhumor.outhustle(US) To do a better job of hustling thanoutinsult(transitive) To surpass in insulting.outinvent(transitive) To surpass in invention; to invent more or better than.outinvest(transitive) To invest (money) better or more profitably than.outjockey(transitive) To outdo; to outvie.outjuggle(transitive) To surpass in juggling; to juggle more or better than.outkeeperAn attachment to a surveyor's compass for keeping tally in chaining.outlabour(transitive) To surpass in labouring; to outwork.outlanderA foreigner or alien.outlastedsimple past and past participle of outlastoutlaunch(transitive) To launch more spacecraft than.outlawdomThe state, condition, or jurisdiction of outlaws; lawlessness; outlaws collectively.outlawingpresent participle and gerund of outlawoutlawishHaving the attributes of or pertaining to outlaws.outlawismThe state of being an outlaw; lawlessness.outlawyer(US, informal) To have a larger or stronger legal team than.outlayingpresent participle and gerund of outlayoutlinearOf or pertaining to an outline; being in, or forming, an outline.outlinger(transitive) To linger longer than; to outstay.outliningpresent participle and gerund of outlineoutlivingpresent participle and gerund of outliveoutlooker(construction) Synonym of lookout (“type of joist”).outlusterAlternative form of outlustre.outlustre(poetic, transitive) To surpass in brightness or lustre; to outshine.outmanage(transitive) To surpass in management; to manage better than.outmannedsimple past and past participle of outmanoutmarvel(transitive) To surpass in marvellousness.outmasterTo overcome; to win or prevail in a competition.outmodingpresent participle and gerund of outmodeoutmuscle(transitive) To surpass in a contest involving strength.outnigger(transitive, offensive, derogatory) To outsmart or deceive.outnumber(transitive, stative) To be more in number than somebody or something.outpacingpresent participle and gerund of outpaceoutparcelA plot of land in a commercial shopping center development reserved for the later construction of smaller buildings, often restaurants.outparish(historical) A parish lying outside the walls of, or in a remote part of, a town.outpedant(transitive) To surpass in pedantry.outpicketA military picket or outpost.outplacedsimple past and past participle of outplaceoutplaceeAn employee who is outplaced.outplacer(business) A company that outplaces an employee.outplayedsimple past and past participle of outplayoutplease(transitive) To surpass in pleasing.outpoison(transitive) To surpass in poisoning.outpostedPosted to an outpost.outpourerOne who outpours.outpowersthird-person singular simple present indicative of outpoweroutpraise(transitive) To surpass in praising.outpreach(transitive) To surpass in preaching.outpsycheAlternative form of outpsych.outpunish(transitive, rare) To surpass in punishing.outputtedsimple past and past participle of outputtoutputterSomething that outputs.outquench(archaic, transitive) To quench entirely; to extinguish.outracingpresent participle and gerund of outraceoutragingpresent participle and gerund of outrageoutrangedsimple past and past participle of outrangeoutrankedsimple past and past participle of outrankoutreason(transitive) To surpass in reasoning; to reason better than.outreckon(transitive) To surpass in reckoning or computation.outredden(transitive, poetic) To surpass in redness.outreliefAlternative form of out-relief.outrenessAlternative form of outréness.outreport(transitive) To surpass in reporting.outriddenpast participle of outrideoutridersplural of outrideroutridingpresent participle and gerund of outrideoutriggedsimple past and past participle of outrigoutrigger(nautical) Any of various projecting beams or spars that provide support for a sailing ship's mast.outrovert(nonstandard, rare) Extrovert.outrunnerAn offshoot; a branch.outrushedsimple past and past participle of outrushoutrushesthird-person singular simple present indicative of outrushoutsailedsimple past and past participle of outsailoutscheme(transitive) To surpass in scheming.outscoredsimple past and past participle of outscoreoutscoresthird-person singular simple present indicative of outscoreoutscrape(intransitive, Scotland, obsolete) To escapeoutscream(transitive) To surpass in screaming.outsearch(transitive) To surpass in searching.outsentry(military) A sentry who guards the entrance or approach to a place.outsetter(Scotland, obsolete) A publisher.outshadowovershadow (to make to seem insignificant)outshinedsimple past and past participle of outshineoutshinerOne who or that which outshines another.outshinesthird-person singular simple present indicative of outshineoutshowedsimple past of outshowoutshower(transitive, now rare) To produce a greater shower than; to dispense in greater quantities than.outshriek(transitive) To surpass in shrieking.outshrill(transitive) To surpass in shrilling; to cry louder than.outsidersplural of outsideroutskirtsThe area surrounding a city or town; suburb.outsmartsthird-person singular simple present indicative of outsmartoutsmooth(transitive, poetic) To smooth out; to make smooth.outsnatch(transitive) To surpass in snatching.outsoaredsimple past and past participle of outsoaroutsource(chiefly US, business, management, transitive) To transfer the management or day-to-day execution of a business function to a third-party service provider.outspokenSpeaking, or spoken, freely, openly, or boldly; vocal; frank.outsprangsimple past of outspringoutspread(ambitransitive) To spread out; expand; extend.outspring(intransitive) To spring out.outsprint(transitive) To sprint faster than.outsquawk(transitive, rare) To squawk louder than; to surpass in squawking.outstable(rail transport, transitive) To park (a rail vehicle) in a station, siding or other location away from the (main) depot.outstaredsimple past and past participle of outstareoutstater(US) Someone from a different state.outstayedsimple past and past participle of outstayoutstayer(rare) One who outstays.outstrain(transitive) To outdo by straining.outstreakAn outward streak.outstream(intransitive) To stream outward.outstreet(dated, normally in plural) A street remote from the centre of a town.outstride(transitive) To surpass in striding, to stride faster or longer.outstrike(transitive) To strike faster or harder than.outstripsthird-person singular simple present indicative of outstripoutstrodesimple past of outstrideoutstrokeAn outward stroke; specifically, in a steam engine or other engine, a stroke in which the piston is moving toward the crankshaft.outstrucksimple past of outstrikeoutstupid(transitive, informal) To surpass in stupidity.outsufferTo exceed in suffering.outtackle(transitive, sports) To surpass in tackling.outthrustSomething that extends outwards, especially such an outcrop of rockouttongue(transitive) To make more noise than, especially in speaking.outtravel(transitive) To travel more or greater thanoutvotingpresent participle and gerund of outvoteoutvoyage(transitive) To voyage further or longer than.outwaitedsimple past and past participle of outwaitoutwalkedsimple past and past participle of outwalkoutwalkera person who walks next to, in front of, or behind a parade floatoutwander(intransitive) To go out wandering; to roam beyond bounds.outwarble(transitive) To surpass in warbling; to outsing.outwardlyExternally or on the outside, or on the surface.outweighsthird-person singular simple present indicative of outweighoutwinter(transitive) To keep (livestock) outdoors during the winter.outwittalThe act of outwitting somebody.outwittedsimple past and past participle of outwitoutwitterOne who outwits another.outworkerA subcontractor who carries out work at an off-site facility.outwrench(transitive) To wrench out or outward.ouverture(music) Uncommon form of overture.ovalbumenAlternative form of ovalbumin.ovalbumin(biochemistry) A glycoprotein which is the primary constituent of egg white.ovaliformoviform; egg-shapedovamboite(mineralogy) An isometric-hextetrahedral gray mineral containing arsenic, copper, gallium, germanium, iron, molybdenum, sulfur, tin, tungsten, vanadium, and zinc.ovariolarRelating to an ovarioleovariolesplural of ovarioleovarylessLacking ovaries.ovastacin(biochemistry) An astacin found in oocytes, involved in the hardening of the zona pellucidaovationalOf or relating to ovation.ovenproof(of a dish) Suitable for use in an oven, without being damaged by the heat.overabuseExcessive abuse.overactedsimple past and past participle of overactoveractor(acting) Someone who overacts.overadapt(ambitransitive) To adapt excessively.overadorn(transitive) To adorn excessively.overagingIn metallurgy: excessive heat-treatment of an alloy that has undergone precipitation hardening.overalertExcessively alert.overalign(computing) To organise data with alignment greater that a compiler can handleoveralledWearing overallsoveramped(informal) Very excited, especially as a result of ingesting amphetamines.overapply(transitive) To apply to excess.overargue(ambitransitive) To argue excessively.overawful(obsolete) Excessively awful (awe-inspiring or reverential).overawingpresent participle and gerund of overaweoverbakedsimple past and past participle of overbakeoverbatheTo bathe excessively.overbitesplural of overbiteoverblame(transitive) To blame excessively.overbleed(intransitive) to bleed excessivelyoverblindExcessively blind.overbloom(botany) To produce an excessive amount of flowers or algae.overblownOf exaggerated importance; too heavily emphasized, hyped, etc.overboard(nautical) Outside of a boat; in the water.overboast(ambitransitive) To boast excessively.overboostTo increase an engine's intake manifold pressure to higher levels than it is designed for.overbootsplural of overbootoverboredsimple past and past participle of overboreoverbornesimple past and past participle of overbearoverbossyExcessively bossy.overboundsimple past and past participle of overbindoverbrake(ambitransitive) To brake (a vehicle) excessively; to apply the brake too much.overbrand(marketing) To use too many brands (proprietary names in marketing).overbraveExcessively brave.overbreak(intransitive) To cave in near the edge of an excavation.overbreedTo breed excessively.overbribe(transitive) To give too large a bribe to.overbriefExcessively brief.overbroilTo broil excessively.overbrokesimple past of overbreakoverbrood(transitive, poetic) To brood over.overbrown(cooking, transitive) To brown too much.overbrushto brush excessivelyoverbuild(ambitransitive) To perform excessive construction on a building or in an area.overbuiltsimple past and past participle of overbuildoverbulkyExcessively bulky.overburntsimple past and past participle of overburnoverburst(rare) An excessively intense burst; a superburst.overcallsthird-person singular simple present indicative of overcallovercarry(transitive) To carry too far, or beyond the proper point.overcarve(transitive) To carve too much or too deeply.overcastsplural of overcastovercatch(transitive, UK dialectal) To overtake.overcheckA check pattern that is superimposed upon another patternoverchiefA higher-ranking chief; a leader of several chiefs.overchill(transitive) To chill too much.overcivilExcessively civil.overclaim(transitive) To claim too much.overclassA powerful, privileged social class.overclean(transitive) To clean to an excessive degree.overclear(transitive) To make too clear, or translucent.overclerkA clerk who also supervises one or more underclerks.overcloakA cloak worn over other clothingoverclock(computing, transitive) To run a processor (CPU), or any electronic logic device, at a speed higher than is recommended by the manufacturer.overcloseIn too great a proximity.overclothAny of various overgarments that consist primarily of a large cloth worn over the clothes.overcloud(ambitransitive) To cover, or become covered, with clouds.overcoachTo coach too much.overcoatsplural of overcoatovercolor(transitive) Alternative spelling of overcolour.overcomerOne who overcomes.overcomesthird-person singular simple present indicative of overcomeovercooksthird-person singular simple present indicative of overcookovercount(transitive) To count more of something than are actually present, or to count one thing disproportionately more than anotherovercover(transitive) To cover over.overcreepTo creep over or across.overcroftA room between the vaulting and the roof of a churchovercropsthird-person singular simple present indicative of overcropovercross(transitive) to cross over; traverseovercrowdTo fill beyond reasonable limits, with people, animals, objects or information.overcrueloverly or excessively cruelovercrustTo cover with a crust.overdeferTo defer a larger amount than one should.overdeity(rare, science fiction, fantasy, video games) A superior or supreme deity.overdenseExcessively dense; especially more dense than is necessary to form a galaxy.overdight(obsolete) Adorned; decked over; overspread; covered over.overdoingpresent participle and gerund of overdooverdopedExcessively doped.overdosedsimple past and past participle of overdoseoverdoserOne who overdoses.overdosesplural of overdoseoverdraft(uncountable) The act of overdrawing a bank account.overdrain(transitive) To drain excessively.overdranksimple past and past participle of overdrinkoverdrape(transitive) To drape (something) over something else.overdrawnpast participle of overdrawoverdream(rare) To dream (about) excessively.overdreep(transitive, obsolete) To fall or droop over; overshadow.overdress(intransitive) To wear too many clothes for a particular occasion.overdriedsimple past and past participle of overdryoverdrift(of a windmill) Having gearing that turns the millstone by means of a pole that rises above it.overdrink(ambitransitive) To drink to excess.overdrive(transitive) To drive too hard, or far, or beyond strength.overdrovesimple past of overdriveoverdrown(transitive, obsolete) To drench or wet to excess.overeagerExcessively eager.overeatenpast participle of overeatovereaterOne who eats too much; particularly one who does so regularly.overedger(sewing) An overlocker.overemoteTo display emotion excessive for the situation.overempty(transitive) To make too empty; to exhaust.overenjoy(transitive) To enjoy too much.overequip(transitive) To furnish with too much equipment.overexactToo exact; overscrupulous; pedantic; overprecise.overexertTo exert (oneself) to an excessive degree.overfancyExcessively fancy.overfavor(transitive) To favor excessively; to treat with undue preference.overfillsthird-person singular simple present indicative of overfilloverfired(comparable, ceramics) Fired at a high (or excessively high) temperature.overfloatTo float aboveoverfloodTo flood or fill completely; to overflow.overflownpast participle of overflyoverflowsplural of overflowoverflushSurplus assets.overfocusTo focus excessively (on a particular subject to the exclusion of others)overforceExcessive force; violence.overfrailExcessively frail.overfrankTo pay excessive franking credits.overfrontA false overshirt, jacket, or vest that is attached to the bodice or shirt of a garment.overfussyExcessively fussy.overglazeThe outer layer or coat of glaze on a piece of potteryovergloomTo cause gloom on; to make gloomy.overgloss(transitive) To make (paper, etc.) too glossy.overgodlyExcessively godly.overgoingpresent participle and gerund of overgoovergorgeTo gorge to excess.overgraceTo grace excessively.overgrade(bridge-building) Having the truss above the roadway.overgrain(art) To apply an additional layer of colour to graining, or imitation woodgrain.overgraze(transitive) to graze land excessively, to the detriment of the land and its vegetationovergreatExcessively great.overgreedExcessive greed.overgreen(transitive, poetic) To cover with greenery or a green color.overgrind(transitive) To grind excessively.overgroom(transitive, sometimes intransitive) To groom excessively.overgrossExcessively gross.overgroup(mathematics) A supergroup.overgrownHaving large numbers of plants which have become too big, and are hence spoiling the picturesqueness of a garden.overgrowsthird-person singular simple present indicative of overgrowoverhangsplural of overhangoverhappyExceedingly happy.overharshExcessively harsh.overhasteExcessive, often undue haste.overhatedGiven an excessive amount of hate; getting more hate than it deserves.overhaulsplural of overhauloverheadsplural of overheadoverheadyExcessively heady.overheardsimple past and past participle of overhearoverhearsthird-person singular simple present indicative of overhearoverheatsthird-person singular simple present indicative of overheatoverheave(intransitive, obsolete) To overcast.overheavyOverly heavy; being of or having excessive heaviness in weight or other aspects.overhours(dated) Additional hours worked; overtime.overhouseStretched along the roofs of buildings, rather than on poles or underground.overhurry(ambitransitive) To hurry excessively.overhypedsimple past and past participle of overhypeoverissue(transitive) To issue too much or too many of.overjadedExcessively jaded.overjudge(transitive) To judge excessively or too harshly.overlaborAlternative form of overlabour.overladedsimple past and past participle of overladeoverladenPacked heavily, especially beyond normal capacity; overloaded.overlargeExcessively large; too big; oversize.overlayedsimple past and past participle of overlayoverlayerA layer of adatoms adsorbed onto a surface, as onto the surface of a single crystal.overleapsthird-person singular simple present indicative of overleapoverleaptsimple past and past participle of overleapoverlearnTo learn (something) more than is necessary; to study excessively, to take (something) too much to heart.overleave(transitive) To leave (something) over; cause to remain or be left.overlevel(video games) In role-playing and similar games, to attain a higher experience level than appropriate for a given battle or task.overlight(transitive) To illuminate too brightly.overlimit(finance) Having more money being charged on a credit card than what is available as credit.overliver(puristic, otherwise obsolete) A survivor.overloadsplural of overloadoverloftyExcessively lofty.overlooksthird-person singular simple present indicative of overlookoverlordsplural of overlordoverloyalExcessively loyal.overlustyToo lusty or lively.overlyinglying over or upon something elseovermarch(transitive) To cause to march too far, or too often; to exhaust by marching.overmatch(transitive, intransitive) To match more than intended.overmeritExcessive merit.overmerryExcessively merry.overminedDepleted by excessive mining.overmodedAffected by overmodulationovermoistExcessively moist.overmoodyExcessively moody.overmouldAlternative form of overmold.overmountMounted over something else.overmournTo mourn excessively.overnightDuring or throughout the night, especially during the evening or night just past.overnoise(obsolete, rare, transitive) To overpower with noise.overnurseTo nurse excessively.overoaked(wine) Excessively oaked.overobeseExcessively obese.overorder(ambitransitive) To order too much or too many.overpaintTo color or describe too strongly.overpayerOne who overpays.overpedal(music, intransitive) To overuse the sustaining pedal of a piano, causing the notes to sound too loud.overpickyExcessively picky or discerning.overpiousExcessively pious.overpitch(transitive) To give too high a pitch to.overplace(transitive) To place too high in a ranking.overplaidA plaid pattern that arises from color woven into a fabric that has another, different woven texture.overplainExcessively plain.overplant(intransitive) To plant too many plants (of any particular crop).overplateIn armour, a large pauldron protecting the shoulder, or a cubitiere protecting the elbow.overpluckTo pluck something too much, usually one's eyebrowsoverplumpExcessively plump.overpoise(chiefly figurative) That which outweighs; excessive weight.overpower(transitive) To subdue someone by superior force.overpress(transitive) To bear upon (someone or something) with irresistible force; to crush, to overwhelm.overpriceto give a commodity an excessive priceoverprime(transitive) To prime with too much fuel.overprint(philately) The addition of new text on a previously printed stamp, usually to add a surcharge or change the face value.overprize(transitive) To prize excessively; to overvalue.overproofPossessing a higher proportion of alcohol than proof spirit.overproudExcessively proud.overprove(transitive) to prove excessively or beyond what is asked or requiredoverprune(transitive, horticulture) To prune too much.overpulse(electronics) An electric pulse that spikes above normal operating levels.overpunch(transitive, computing) To punch (some value or pattern) over an existing pattern on paper tape.overqueen(rare) A superior or supreme queen; a female overking.overquell(transitive) To quell or subdue completely; gain or have power over.overquickToo quick; overly quick.overquietExcessively quiet.overquote(ambitransitive) To give a quotation (price estimate) that is too high.overrakedsimple past and past participle of overrakeoverrangeInput to an instrument beyond the range of values it is designed to handle.overratedGiven an undue amount of credit for quality or merit in a field; not necessarily related to popularity.overraterOne who gives too high a rating.overratesthird-person singular simple present indicative of overrateoverreach(ambitransitive) To reach above or beyond, especially to an excessive degree.overreactTo react too much or too intensely.overrelax(transitive) To relax excessively.overridenMisspelling of overridden.overriderOne who or that which overrides.overridesthird-person singular simple present indicative of overrideoverrigidToo rigid or severe.overripenTo ripen too much; to become overripe.overroast(transitive) To roast too much.overroughExcessively rough.overroundThe margin taken by the bookmaker in a gambling operation.overruledsimple past and past participle of overruleoverrulerSomeone or something thay controls, governs, or determines.overrulesthird-person singular simple present indicative of overruleoversaltyExcessively salty.oversatedExcessively sated.oversauce(transitive) To cover (food) with too much sauce.oversaucyExcessively saucy.oversaverOne who oversaves.overscaleOut of scale; much too large for the context in which it existsoverscareTo scare too much.overscarfA decorative scarf worn over clothing.overscent(transitive) To give too much scent to (something or someone); to scent excessively.overscoreSynonym of overbar.overseersplural of overseeroversenseTo sense or detect too much, or more than is actually present.overserve(transitive) To serve too much (especially alcohol to an intoxicated person).oversewedsimple past of oversewoversexedHaving a greater than normal sexual appetiteovershadeTo cast a shadow over, to overshadow.overshakeTo shake too much.overshape(transitive) To transform; alter.overshare(transitive) To share too much or in excess.oversharpExcessively sharp.overshaveTo shave excessively.oversheetA sheet placed over the top of something.overshift(mineralogy) The amount of displacement in the layers in a crystal lattice that places the layers too far apart for molecular bonding.overshine(poetic) To shine over or upon; to illumine.overshirtA shirt intended to be worn over other clothes.overshockTo shock too much.overshoesplural of overshoeovershooksimple past of overshakeovershoot(countable) The amount by which something goes too far.overshortExcessively short.oversightAn omission; something that is left out, missed, or forgotten.oversizedVery large; especially of something larger than normal for its type.overskies(science fiction) interplanetary, intergalactic.overskirtA skirt worn visibly, especially over another layer, such as a petticoat.overslackExcessively slack.oversleep(intransitive) To sleep for longer than intended.oversleptsimple past and past participle of oversleepoverslide(transitive) To slide over or past.overslungslung (or supported) over somethingoversmallExcessively small.oversmoke(transitive) To smoke (bees, food being cured, etc.) excessively.oversocksplural of oversockoversolar(astronomy) Describing a concentration or abundance of a chemical element or isotope greater than that found in the Sun.overspace(transitive, typography) To separate with too much space; to set too far apart.overspeakTo exceed in speaking.overspeed(intransitive) To travel excessively fast or beyond the permitted rate.overspellTo make spelling mistakes by adding extra letters.overspendTo spend too much money; especially, to spend more than one earns.overspentsimple past and past participle of overspendoverspice(transitive) To add too much spice to (a dish).overspicyExcessively spicy.overspillThat which spills over.oversplit(gymnastics) To perform such a split.overspokesimple past of overspeakoversprayIn spray painting, the spray that goes outside the area being painted (necessary to ensure coverage at the edge).overstack(transitive) To stack too high.overstaff(transitive) To furnish with too many staff.overstage(theater, of lighting, machinery etc) Above the stage.overstain(transitive) To stain the surface of; besmear.overstaleExcessively stale.overstampTo apply a stamp over an existing image or text.overstand(transitive) To stand too strictly on the demands or conditions of.overstare(obsolete) To stare wildly.overstate(transitive) To state or claim too much.overstaysthird-person singular simple present indicative of overstayoversteamTo steam too much.oversteep(transitive) To steep for too long.oversteerto lose the control of one's vehicle in a corner due to rear wheels sliding and not following the front wheelsoverstepsthird-person singular simple present indicative of overstepoverstiffExcessively stiff.overstock(transitive) To stock to an excessive degree.overstoke(transitive) To stoke excessively, creating too large a fire in a fireplace, furnace, firebox, etc.overstoreTo overstock; to save more than is needed.overstoryThe upper portion of a community of plants, above the understory.overstoutExcessively stout.overstrapA strap running above something.overstrawObsolete form of overstrew.overstrewTo strew or scatter over.overstrowAlternative form of overstrew.overstudyTo study excessivelyoverstuff(transitive) To stuff to excess.overswarm(transitive) To swarm over; to overrun.overswear(intransitive) To swear excessively; to make too many oaths.oversweep(transitive) To sweep over; to cover by sweeping.oversweetToo sweet; excessively sweet.overswell(ambitransitive) To swell or rise above (something, especially the rim of a container, the sides of something hollow, etc.).overswift(rare) Overly swift.overswing(transitive) To swing too far.overswirl(transitive) To swirl excessively.oversworesimple past of overswearovertakenpast participle of overtakeovertakerOne who overtakes.overtakesthird-person singular simple present indicative of overtakeovertaxedsimple past and past participle of overtaxoverteach(transitive, intransitive) To teach too much.overtemptTo tempt exceedingly, or beyond someone's resistance.overtenseExcessively tense.overthinkTo think or analyze too much.overthrewsimple past of overthrowoverthrow(transitive) To bring about the downfall of (a government, etc.), especially by force; to usurp.overtightExcessively tight.overtildeA tilde placed over another character.overtimerAn employee who works overtime.overtimesplural of overtimeovertiredsimple past and past participle of overtireovertitleTo give too high a title or status to.overtnessThe state of being overt; openness.overtonesplural of overtoneovertower(transitive) To tower above or over.overtrace(transitive) To trace over.overtrack(rail transport) Over and above a railway track.overtradeTo trade beyond one's capital; to buy goods beyond the means of paying for or selling themovertrain(ambitransitive) To train too much or too long.overtread(transitive) To tread over or upon.overtreat(medicine, transitive) To subject to excessive medical treatment, often to such an extent as to cause adverse effects.overtrick(bridge) A trick won by the declarer's side which exceeds the amount of the contractovertrump(card games) To play a higher trump card than the previous one in a trick.overtrustTo trust too much.overtunedTuned or adjusted so as to be excessive (in terms of some quality), especially:overtunicA tunic worn over other clothing.overturedsimple past and past participle of overtureoverturesplural of overtureoverturnsthird-person singular simple present indicative of overturnovertutorTo tutor excessively.overtwistTo twist excessively.overusageexcessive usageoverusingpresent participle and gerund of overuseovervalueTo assign an excessive value to something.overvault(transitive) To leap over.overviewsplural of overviewovervividExcessively vivid.overvoice(transitive) To voice (a sound) too strongly.overvoterOne who overvotes.overwatch(transitive) To watch over.overwaterBy or across water, especially of travel.overwearsthird-person singular simple present indicative of overwearoverweary(transitive) To weary too much; to tire out.overweigh(transitive, archaic) To exceed in weight, outweigh; to preponderate; to weigh down.overwhelmTo engulf, surge over and submerge.overwiden(ambitransitive) To make or become too wide.overwidthWider than is standard or (transport, law, of a vehicle) wider than is allowed.overwield(transitive) To wield over or in excess; overpoweroverwordyExcessively wordy.overworksthird-person singular simple present indicative of overworkoverworldThe celestial world.overwoundsimple past and past participle of overwindoverwrest(transitive, archaic) To wrest or force from the natural or proper position.overwrite(transitive, computing) To destroy (older) data by recording new data over it.overwrotesimple past of overwriteoverwroth(archaic) Excessively angry.overyieldTo yield more than normally, typically when grown with another plant speciesoveryoungExcessively young.ovibovineOf or relating to the genus Ovibos.ovicaprid(chiefly archaeology) A domestic sheep or goat.oviductalOf, pertaining to, or occurring in the oviduct.oviferousProducing or bearing eggs.ovigenous(biology) that produces ova or eggsovigerouscarrying or bearing eggs.ovijector(biology) The muscular part of the oviduct of a nematode that propels the egg through the genital poreovinationThe inoculation of sheep with ovine virus against sheeppox.oviparityThe condition of being oviparous.oviparousDepositing eggs that develop and hatch outside the body as a reproductive strategy.oviraptorAny of several bipedal dinosaurs, of the genus Oviraptor, from the late Cretaceous period.oviscapte(entomology) The oviscape or ovipositor.ovispirin(biochemistry) Any of a group of ovine antimicrobial and cytotoxic cathelicidinsovococcalRelating to ovococciovococcus(microbiology) An ellipsoid-shaped bacteriumovoflavin(dated, biochemistry) riboflavinovologistOne who studies ovology.ovomucoid(biochemistry) A protein, present in egg white, which, unlike ovalbumin, is heat-stableovostatin(biochemistry) Any of a class of proteinase inhibitors found in hens' eggs.ovotestesplural of ovotestisovotestis(biology) A gonad with characteristics of both ovaries and testicles. Considered an intersex condition in humans and some other animals.ovulatingpresent participle and gerund of ovulateovulation(physiology) The release of an ovum from an ovary.ovulatorypertaining to ovulation; ovulatingowdaciousPronunciation spelling of audacious.owenettid(zoology) Any extinct parareptile in the family Owenettidae.ownednessThe quality of being owned.ownerlessHaving no owner.ownershipThe state of having complete legal control of something; possession; proprietorship.owyheeite(mineralogy) An orthorhombic-dipyramidal gray-white mineral containing antimony, bismuth, lead, silver, and sulfur.oxaborole(organic chemistry) A five-membered heterocycle having three carbon atoms, one oxygen atom, one boron atom and two double bonds; it, and its derivatives, are formally derived from an oxazole by replacing the nitrogen atom with one of boronoxacephem(organic chemistry) A derivative of cephem in which an oxygen atom has been substituted for sulfur; the basis for a group of antibioticsoxaceprolA particular kind of anti-inflammatory drug that is used to treat osteoarthritis.oxachelinA particular iron chelator and antifungal agent isolated from Streptomycesoxacillin(pharmacology) A narrow-spectrum beta-lactam antibiotic made by chemical modification of penicillin and administered in the form of its hydrated sodium salt C₁₉H₁₈N₃NaO₅S·H₂O to treat infections caused by penicillin-resistant staphylococci.oxacyclic(organic chemistry) Describing any heterocycle having one or more oxygen atoms in the ringoxadiazol(organic chemistry, especially in combination) Any univalent radical derived from an oxadiazoleoxadiazonThe herbicide 5-tert-butyl-3-(2,4-dichloro-5-isopropoxyphenyl)-1,3,4-oxadiazol-2(3H)-oneoxalaemiaAlternative form of oxalemia.oxalamide(organic chemistry) The amide of oxalic acid; any N-derivative of this compoundoxalantin(organic chemistry) A nitrogenous substance, C₆H₄N₄O₅, obtained by the reduction of parabanic acid.oxalurate(obsolete, chemistry) A salt of oxaluric acid.oxamidine(organic chemistry) One of a series of bases containing the amido and isonitroso groups united to the same carbon atom.oxanamideAn anxiolytic and muscle relaxant.oxanilate(chemistry) A salt of oxanilic acid.oxanilide(organic chemistry) A white crystalline substance resembling oxanilamide, obtained by heating aniline oxalate, and regarded as a double anilide of oxalic acid; diphenyl oxamide.oxaprozinA nonsteroidal anti-inflammatory drug.oxathiane(organic chemistry) Any of three isomeric six-membered saturated heterocycles containing four carbon atoms, one oxygen and one sulfur atomoxathiine(organic chemistry) The unsaturated six-membered heterocycle having four carbon atoms, one oxygen atom, one sulfur atom and two double bondsoxathiole(organic chemistry) An unsaturated five-membered heterocycle having three carbon atoms, one oxygen atom, one sulfur atom and one double bondoxatomideA particular antihistamine drug derived from piperazine.oxazepane(organic chemistry) A saturated seven-membered heterocycle containing five carbon atoms, one nitrogen atom and one oxygen atomoxazepine(organic chemistry) A seven-membered unsaturated heterocycle containing five carbon atoms, one nitrogen and one oxygen atom, and three double bonds; any derivative of this compoundoxazinium(organic chemistry) A cation derived from an oxazine or related compoundoxazinone(organic chemistry) Any of several isomeric heterocyclic ketones derived from oxazineoxazocane(organic chemistry) A saturated eight-membered heterocycle containing six carbon atoms, one nitrogen atom and one oxygen atomoxazocine(organic chemistry) An eight-membered, unsaturated heterocycle containing six carbon atoms, one oxygen and one nitrogen atom, and three double bonds, but especially 1,3-oxazocine and 1,4-oxazocineoxazoline(organic chemistry) An unsaturated heterocyclic compound containing a five-membered ring, one double bond, one nitrogen and one oxygen atom; any derivative of this compoundoxazolium(organic chemistry) A cation derived from a oxazoleoxazolone(organic chemistry) A five-membered heterocycle containing three carbon atoms, one nitrogen atom, one oxygen atom, a carbonyl group and a double bondoxepinone(organic chemistry) Any ketone derived from oxepineoxepinoxy(organic chemistry) A radical derived from oxepine having a carbonyl group in position 2oxetoroneAn antimigraine drug.oxidationThe combination of a substance with oxygen.oxidative(chemistry) Of, relating to, or produced by oxidation.oxidisersplural of oxidiseroxidisingpresent participle and gerund of oxidiseoxidizersplural of oxidizeroxidizingThat oxidizes.oximation(organic chemistry) Reaction with, or conversion into an oximeoximetersplural of oximeteroximetricRelating to oximetryoxindanac(pharmacology) A nonsteroidal anti-inflammatory drug.oxoacetic(organic chemistry) glyoxylicoxoborate(inorganic chemistry) Any mixed oxide and borateoxocarbon(organic chemistry) Any organic compound containing only atoms of carbon and oxygenoxocrinol(organic chemistry) A linear terpenoid derived from the seaweed Cystoseira crinita, 12-hydroxy-6,10-dimethyldodeca-6,10-dien-2-oneoxodipine(pharmacology) A type of calcium channel blocker.oxoferryl(inorganic chemistry) Relating to high-valent iron ions directly bonded to oxygenoxohalide(chemistry) Any of several anions or complexes that contain both an oxide and a halide groupoxoiodide(chemistry) Any oxohalide in which the halide is iodideoxolamineA cough suppressant.oxolation(inorganic chemistry) A condensation reaction in which an oxo bridge is formed between two metal centres.oxomutase(biochemistry) Any mutase that modifies oxygen-containing heterocycles (typically converting an oxirane to an oxetane)oxophilic(chemistry) Exhibiting oxophilicityoxosilane(chemistry) siloxaneoxpeckersplural of oxpeckeroxyacetichydroxyaceticoxybiotic(biology) That lives in an environment rich in oxygenoxybromic(chemistry) Pertaining to, or designating, certain compounds of oxygen and bromine.oxycationA polyatomic ion that has at least one oxygen atom and an overall positive charge.oxychoridAny weevil in the family Oxychoridae, a synonym of the belid tribe Oxycorynini.oxycodone(organic chemistry, pharmacology) An addictive, semisynthetic opioid (trademark OxyContin) that is similar to morphine in effect and structure; C₁₈H₂₁NO₄.oxycontinAlternative letter-case form of OxyContin.oxycotton(slang) Oxycodone used as a recreational drug.oxycymene(chemistry) hydroxy cymene; carvacroloxyferryl(chemistry, especially in combination) A radical containing ferryl iron and an oxygen atom Feᴵⱽ-O; found especially in forms of hemeoxygenase(biochemistry) An enzyme which catalyses biochemical reactions with oxygen.oxygenate(transitive) To treat or infuse with oxygen.oxygenian(mineralogy) Containing oxygen.oxygeniseAlternative spelling of oxygenize.oxygenous(obsolete) oxygenicoxygraphyThe monitoring of the concentration or partial pressure of oxygen in the respiratory gases.oxyhalide(inorganic chemistry) Any anion (and corresponding salt) in which a central atom is bonded to both oxygen and a halogenoxyhexactA hexact with axes running to a point.oxyiodide(chemistry) A compound containing oxygen and iodine.oxyliquitAny of a class of explosive materials consisting of a mixture of liquid oxygen and fuel.oxymetricMisspelling of oximetric.oxymoronsplural of oxymoronoxymorous(rare) Synonym of oxymoronic.oxypendylA particular antiemetic and antipsychotic.oxyphenol(chemistry) A phenol produced by the distillation of catechin; oxyphenic acid or pyrocatechin.oxyphilicHaving an affinity for oxygen.oxyphonia(medicine) shrillness or high pitch of the voiceoxypurine(organic chemistry) Any oxidised form of a purine, such as hypoxanthine, xanthine or uric acidoxyruncid(zoology) Any sharpbill in the family Oxyruncidae.oxysterol(organic chemistry) Any of several oxidized derivatives of sterolsoxytactic(biology) Of or pertaining to oxytaxisoxytocicsplural of oxytocicoxytocinsplural of oxytocinoxytonizeTo make a word oxytone by dropping the main stress on the final syllableoxytraumatrauma due to excess oxygen, typically received from a hospital ventilatoroysterbedAlternative spelling of oyster bed.oysteringpresent participle and gerund of oysteroysterishoyster-like, especially in colouroystermanA person who cultivates, harvests or sells oystersoystermenplural of oystermanoysterousResembling or relating to oysters.ozocerite(mineralogy) A dark waxy mineral, found associated with petroleum in some sandstones, used to make polishes.ozokeriteAlternative form of ozocerite.ozolinoneA loop diuretic drug, an active metabolite of etozoline.ozonation(chemistry) The act of treating with ozone.ozonelesswithout ozoneozonelikeResembling or characteristic of ozone.ozonisingpresent participle and gerund of ozoniseozonizersplural of ozonizerozostomia(medicine) Bad breath; halitosis.
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