underground

[adv., uhn-der-ground; adj., n., v. uhn-der-ground] /adv., ˈʌn dərˈgraʊnd; adj., n., v. ˈʌn dərˌgraʊnd/
adverb
1.
beneath the surface of the ground:
traveling underground by subway.
2.
in concealment or secrecy; not openly:
subversion carried on underground.
adjective
3.
existing, situated, operating, or taking place beneath the surface of the ground.
4.
used, or for use, underground.
5.
hidden or secret; not open:
underground political activities.
6.
published or produced by political or social radicals or nonconformists:
an underground newspaper.
7.
avant-garde; experimental:
an underground movie.
8.
critical of or attacking the established society or system:
underground opinion.
9.
of or for nonconformists; unusual:
an underground vegetarian restaurant.
noun
10.
the place or region beneath the surface of the ground.
11.
an underground space or passage.
12.
a secret organization fighting the established government or occupation forces:
He fought in the French underground during the Nazi occupation of France.
13.
(often initial capital letter) a movement or group existing outside the establishment and usually reflecting unorthodox, avant-garde, or radical views.
14.
Chiefly British. a subway system.
verb (used with object)
15.
to place beneath the surface of the ground:
to underground utility lines.
Origin
1565-75; under- + ground1
Examples from the web for underground
  • Earthquakes may cause the surface to shake but are not a hazard in tunnels deep underground.
  • Truffles belong to the same family as mushrooms, and are grown underground.
  • From time to time a hollow murmur underground or a sudden spirt of flame into the air tells of what is going on beneath our feet.
  • The idea is that the plants will root and make potatoes on any part of the stalk that is underground.
  • They also say it would not end the use of agents but would rather drive the practice underground.
  • They also argue that a ban would not end the use of agents but would rather drive the practice underground.
  • None of those practices have eliminated underground pirate networks on many campuses.
  • When trying to climb across it, he slipped right through, and landed in an underground cavern.
  • Indeed, since the citadel collapsed into a natural underground cistern.
  • There is valet parking and an underground parking structure.
British Dictionary definitions for underground

underground

adjective (ˈʌndəˌɡraʊnd)
1.
occurring, situated, or used below ground level: an underground tunnel, an underground explosion
2.
secret; hidden: underground activities
adverb (ˌʌndəˈɡraʊnd)
3.
going below ground level: the tunnel led underground
4.
into hiding or secrecy: the group was driven underground
noun (ˈʌndəˌɡraʊnd)
5.
a space or region below ground level
6.
  1. a movement dedicated to overthrowing a government or occupation forces, as in the European countries occupied by the German army in World War II
  2. (as modifier): an underground group
7.
the underground, an electric passenger railway operated in underground tunnels US and Canadian equivalent subway
8.
(usually preceded by the)
  1. any avant-garde, experimental, or subversive movement in popular art, films, music, etc
  2. (as modifier): the underground press, underground music
Word Origin and History for underground
adv.

1570s, "below the surface," from under + ground (n.). As an adjective, attested from c.1600; figurative sense of "hidden, secret" is attested from 1630s; adjectival meaning "subculture" is from 1953, from World War II application to resistance movements against German occupation, on analogy of the dominant culture and Nazis. Noun sense of "underground railway" is from 1887 (shortened from phrase underground railway, itself attested from 1834).

Slang definitions & phrases for underground

underground

adjective
  1. Apart from and opposed to conventional society; esp, advocating and representing the hippie and narcotics subculture: The Voice started as a sort of underground newspaper (1953+)
  2. In hiding; concealing one's identity and whereabouts, esp to escape arrest (1820+)