Underground

/ˌʌn.dəˈɡɹaʊnd/ · adjective

Meaning

(not comparable) Below the ground; below the surface of the Earth..

Definitions by Sense

1. (not comparable) Below the ground; below the surface of the Earth.
2. (figurative) Hidden, furtive, secretive.
3. (figurative) Of or relating to an art forms (such as music) or subculture that is outside the mainstream, especially one that is unofficial and hidden from the authorities.
4. Below the ground.
5. Secretly.
6. (geography) The regions beneath the surface of the earth, both natural (eg. caves) and man-made (eg. mines).
7. (chiefly British) Synonym of subway: a railway that is under the ground.
8. (with definite article) A movement or organization of people who resist political convention.

Example Sentences

There is an underground tunnel that takes you across the river.

One of the hidden glories of Victorian engineering is proper drains. Isolating a city’s effluent and shipping it away in underground sewers has probably saved more lives than any medical procedure except vaccination.

These criminals operate through an underground network.

underground music

‘[…]he wrote to me last week telling me about an incredible bitch of a row blazing there on account of someone having been and gone and produced an unofficial magazine called Raddled, full of obscene libellous Oz-like filth. And what I though, what Sammy and I thought, was—why not?’ ‘Why not what?’ said Tom. ‘Why not do the same thing here?’ ‘You mean an underground magazine?’ ‘Yup.’

"In many ways, it showed there was no longer an underground, as such. This proved that there was no longer one society with everyone agreeing how to live . . . The underground had officially come above ground, and consequently no longer existed."

The tunnel goes underground at this point.

London Underground

Synonyms for underground

Antonyms for underground

Related Words

Word Forms

• more underground
• most underground
• under ground
• under-ground
• undergrounds
• undergrounding
• undergrounded

Usage Notes

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

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