Unstable

/ʌnˈsteɪ.bəl/ · adjective

Meaning

Not stable..

Definitions by Sense

1. Not stable.
2. Having a strong tendency to change.
3. Fluctuating; not constant.
4. (figurative) Fickle.
5. (figurative) Unpredictable.
6. (chemistry) Readily decomposable.
7. (physics) Radioactive, especially with a short half-life.
8. (transitive) To release (an animal) from a stable.

Example Sentences

unstable foundation

The structure is too unstable to stand safely.

The hillside at this point is composed of shaly rock overlaid with a peaty loam which carries a growth of heather, and its unstable condition has resulted in two landslides in the course of the railway's history.

The dawn of the oil age was fairly recent. Although the stuff was used to waterproof boats in the Middle East 6,000 years ago, extracting it in earnest began only in 1859 after an oil strike in Pennsylvania.[…]It was used to make kerosene, the main fuel for artificial lighting after overfishing led to a shortage of whale blubber. Other liquids produced in the refining process, too unstable or smoky for lamplight, were burned or dumped.

politically unstable

The political situation remains unstable.

All of the characters in Rocko's Modern Life are anthropomorphic animals of varying species, the vast majority of whom are mentally unstable. Murray said that he matched personalities of his characters to the various animals in the series to form a social caricature.

chemically unstable

Synonyms for unstable

Antonyms for unstable

Related Words

Word Forms

• more unstable
• most unstable
• unstables
• unstabling
• unstabled

Usage Notes

Choose a synonym only when it preserves the intended meaning, tone, and grammar of the full sentence.

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