underground — English Dictionary

Adjective

1. Below the ground; below the surface of the Earth.

   Usage

   • not-comparable

   Synonyms

   subterraneanhypogeanbelowground

   Examples

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

   More examples (1)

   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.

2. Hidden, furtive, secretive.

   Usage

   • Figurative

   Examples

   These criminals operate through an underground network.

   At the time, South Florida had a highly active underground biker culture. Gangs including the Pagans, Outlaws and the Reapers frequently moved through the area.

3. 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.

   Usage

   • Figurative

   Synonyms

   alternativeunconventional

   Antonyms

   mainstream

   Examples

   underground music

   More examples (2)

   ‘[…]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."

Adverb

1. Below the ground.

   Synonyms

   belowground

   Examples

   The tunnel goes underground at this point.

2. Secretly.

   Synonyms

   clandestinelyin secreton the quiet

Noun

1. The regions beneath the surface of the earth, both natural (eg. caves) and man-made (eg. mines).

2. Synonym of subway: a railway that is under the ground.

   Usage

   • UK usage

   Synonyms

   underground railway

   Examples

   London Underground

3. A movement or organization of people who resist political convention.

   Usage

   • with-definite-article

   Synonyms

   resistance

   Examples

   the French underground during World War II

   Victor, please, don't go to the underground meeting tonight.

4. A movement or organization of people who resist artistic convention.

   Usage

   • with-definite-article

   Synonyms

   avant-gardecounterculture

Verb

1. To route electricity distribution cables underground.

   Examples

   One is to underground where no other alternative will work, and this method should be used universally in urban regions as it now is in “downtown” sections.

   More examples (1)

   Also, undergrounding may not eliminate the potential for crashes with other roadside objects, such as trees, walls, buildings, and so forth. [...] When looking at the fesibility of undergrounding utilities, the complete roadside area and nearby adjacent properties should be evaluated for potential roadside obstructions or hazards.

   The utility now wants the network to be undergrounded in the urban areas, which would mean substations with 33 kV distribution swtichgear.

Adjective

1. under the level of the ground

   Synonyms

   belowground

   Examples

   belowground storage areas

   underground caverns

2. conducted with or marked by hidden aims or methods

   Synonyms

   clandestinecloak-and-daggerhole-and-cornerhugger-muggerhush-hushsecretsurreptitiousundercover

   Examples

   clandestine intelligence operations

   cloak-and-dagger activities behind enemy lines

   More examples (7)

   hole-and-corner intrigue

   secret missions

   a secret agent

   secret sales of arms

   surreptitious mobilization of troops

   an undercover investigation

   underground resistance

Noun

1. a secret group organized to overthrow a government or occupation force

   Synonyms

   resistance

   Broader terms

   revolutionary group

2. an electric railway operating below the surface of the ground (usually in a city)

   Synonyms

   metrotubesubway systemsubway

   Broader terms

   railwayrailroadrailroad linerailway linerailway system

   Examples

   in Paris the subway system is called the ‘metro’ and in London it is called the ‘tube’ or the ‘underground’

Adverb

1. in or into hiding or secret operation

   Examples

   the organization was driven underground

2. beneath the surface of the earth

   Examples

   water flowing underground