View synonyms for underground


[ adverb uhn-der-ground; adjective noun verb uhn-der-ground ]


  1. beneath the surface of the ground: ground:

    traveling underground by subway.

  2. in concealment or secrecy; not openly:

    subversion carried on underground.


  1. existing, situated, operating, or taking place beneath the surface of the ground. ground.
  2. used, or for use, underground.
  3. hidden or secret; not open:

    underground political activities.

  4. published or produced by political or social radicals or nonconformists:

    an underground newspaper.

  5. avant-garde; experimental:

    an underground movie.

  6. critical of or attacking the established society or system:

    underground opinion.

  7. of or for nonconformists; unusual:

    an underground vegetarian restaurant.


  1. the place or region beneath the surface of the ground. ground.
  2. an underground space or passage.
  3. a secret organization fighting the established government or occupation forces:

    He fought in the French underground during the Nazi occupation of France.

  4. (often initial capital letter) a movement or group existing outside the establishment and usually reflecting unorthodox, avant-garde, or radical views.
  5. Chiefly British. a subway system.

verb (used with object)

  1. to place beneath the surface of the ground: ground:

    to underground utility lines.



  1. occurring, situated, or used below ground level

    an underground tunnel

    an underground explosion

  2. secret; hidden

    underground activities


  1. going below ground level

    the tunnel led underground

  2. into hiding or secrecy

    the group was driven underground


  1. a space or region below ground level
    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

  2. the underground
    an electric passenger railway operated in underground tunnels US and Canadian equivalentsubway
  3. usually preceded by the
    1. any avant-garde, experimental, or subversive movement in popular art, films, music, etc
    2. ( as modifier )

      underground music

      the underground press

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Word History and Origins

Origin of underground1

First recorded in 1565–75; under- + ground 1

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Example Sentences

Italy may owe some of its seismic activity to carbon dioxide bubbling up from deep underground.

So the group of refuseniks — one of many underground cells plotting freedom — decided to hijack a plane.

From Ozy

Archaeologists had known since 1916 that some holes lurked underground.

Data from NASA’s Dawn orbiter, the study suggests, show signs that it may be harboring an ocean deep underground.

For example, the team found that a seismometer placed 380 meters underground near Auckland, New Zealand, was not only registering human activity, but saw that activity halved during the lockdowns.

But underground classes have Persians getting with the beat.

Atefeh says the participants in the underground classes she attends are mainly young women.

Youssef said the jailings are not only driving the community underground but pushing many to move abroad.

“He literally went underground to hold services,” Moscow-based dissident and journalist Victor Davidoff said in an email.

Unfortunately, the underground tunnels that were used to transport booze and, if necessary, escaping patrons, are off-limits.

All over the world the just claims of organized labor are intermingled with the underground conspiracy of social revolution.

One thing was certain: Grandfather Mole could travel much faster through the water than he could underground.

And when he took an underground stroll he was almost sure to find a few angleworms, which furnished most of his meals.

When a besieged city suspects a mine, do not the inhabitants dig underground, and meet their enemy at his work?

There was a look in his eyes almost as of one coming back from a long and dark journey underground into the light of day.


Related Words




undergraduateunderground movie