underground

adverb
un·​der·​ground | \ ˌən-dər-ˈgrau̇nd How to pronounce underground (audio) \

Definition of underground

 (Entry 1 of 3)

1 : beneath the surface of the earth
2 : in or into hiding or secret operation

underground

noun
\ ˈən-dər-ˌgrau̇nd How to pronounce underground (audio) \

Definition of underground (Entry 2 of 3)

1 : a subterranean space or channel
2 : an underground city railway system
3a : a movement or group organized in strict secrecy among citizens especially in an occupied country for maintaining communications, popular solidarity, and concerted resistive action pending liberation
b : a clandestine conspiratorial organization set up for revolutionary or other disruptive purposes especially against a civil order
c : an unofficial, unsanctioned, or illegal but informal movement or group especially : a usually avant-garde group or movement that functions outside the establishment

underground

adjective
un·​der·​ground | \ ˈən-dər-ˌgrau̇nd How to pronounce underground (audio) \

Definition of underground (Entry 3 of 3)

1 : being, growing, operating, or situated below the surface of the ground
2 : conducted by secret means
3a : existing outside the establishment an underground literary reputation
b : existing outside the purview of tax collectors or statisticians the underground economy
4a : produced or published outside the establishment especially by the avant-garde underground movies underground newspapers
b : of or relating to the avant-garde underground an underground moviemaker an underground theater

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Examples of underground in a Sentence

Adverb

They had been living underground as fugitives.

Noun

I've ridden on the New York subway, the Paris Metro, and the London Underground. joined the underground while still a teenager

Adjective

The drugs are supplied through an underground network. She loves the city's underground music scene.
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Recent Examples on the Web: Adverb

This all happens when the wood is sealed off from oxygen, usually after being buried underground. Hadley Keller, House Beautiful, "This Table Is 100 Million Years Old," 10 Apr. 2019 The centrifuges to enrich uranium can be clandestinely operated underground. Washington Post, "Closing North Korea’s vast nuclear program poses challenges," 9 June 2018 Crews also have installed satellite communication systems in several hospitals and all of Puerto Rico’s 78 municipalities, and placed nearly half of 500 miles worth of optic fiber underground, Rossello said. Danica Coto, The Seattle Times, "Puerto Rico unveils new emergency preparations after Maria," 11 Sep. 2018 Simone and Rasmus magically survived five years underground. Rebecca Farley, refinery29.com, "Would Simone & Rasmus Have Survived Their Five-Year Bunker Stay In The Rain?," 7 May 2018 Regarding the deed agreement, Hruby said the U.S. government is responsible for any unexpected environmental problems found underground. Bob Sandrick, cleveland.com, "Brecksville City Council approves agreement with Independence firm to redevelop former Veterans Affairs hospital property," 13 Mar. 2018 Putting the antineutrino detector five to 10 meters underground and fairly close to a reactor might solve this problem, says Steven Dazeley of Lawrence Livermore National Laboratory, who led a 2016 analysis of noise issues facing WATCHMAN. Jesse Emspak, Scientific American, "Detection of Ghostly Particles Could Unmask Illicit Nuclear Weapons," 1 May 2017 When that purchased occurred in 2010, the energy industry was focused on, among other things, discoveries of huge, cheaply accessible reservoirs of natural gas deep underground in shale formations in the U.S. and abroad. Joe Taschler, Milwaukee Journal Sentinel, "GE selling distributed power unit, which includes Waukesha site, for $3.25 billion," 25 June 2018 On March 23, 1971, the Soviet Union set off three Hiroshima-scale nuclear blasts deep underground in a remote region some 1,000 miles east of Moscow, ripping a massive crater in the earth. Sharon Weinberger, Smithsonian, "How Soviet Bomb Tests Paved the Way For U.S. Climate Science," 7 May 2018

Recent Examples on the Web: Noun

Since 2003, Unsound, which now has iterations in cities ranging from New York to Belarus, has brought the best of the avant-garde electronic and experimental underground to Krakow, Poland. Vogue, "Forget Coachella: These Far-Flung Alternatives Are Pushing Festival Style Forward," 9 Mar. 2019 Recently, though, the European Space Agency’s Mars Express satellite changed that, by finding some of the first evidence of Martian water underground. Avery Thompson, Popular Mechanics, "Spacecraft Discovers Hints of Martian Groundwater," 4 Mar. 2019 That has kept a portion of the trade underground, although one industry insider said black-market transactions had slowed in recent weeks simply because the record-high price of dollars was finally having an impact on demand. Asa Fitch, WSJ, "Iran Struggles to Rein In Illicit Trade in Dollars," 28 Aug. 2018 Earlier this year, researchers documented several underground services that sold counterfeit signing credentials that are unique to each buyer. Dan Goodin, Ars Technica, "Stolen certificates from D-Link used to sign password-stealing malware," 10 July 2018 Frozen Gold New Smyrna Beach, Florida Look, hipster places that source milk from cows that only listen to the National and other underground bands have their place. Ac Shilton, Outside Online, "The Best Ice Cream in the U.S.," 5 July 2018 The British Cave Rescue Council, a voluntary underground rescue operation, has been in touch with the British divers who located the boys. Author: Shibani Mahtani, Anchorage Daily News, "Rescue of Thai youth soccer team trapped in cave could take months, warn officials," 3 July 2018 The British Cave Rescue Council, a voluntary underground rescue operation, has been in touch with the British divers who located the boys. Shibani Mahtani, Washington Post, "Rescue of Thai youth soccer team trapped in cave could take months, warn officials," 3 July 2018 There’s hardly the need when the underground of desire is a wild, open range in our pornography. David Thomson, WSJ, "Farewell My Lovely?," 14 Dec. 2018

Recent Examples on the Web: Adjective

Compounding the matter, gas producers now use a process called hydraulic fracturing, which pumps huge amounts of water and chemicals underground to loosen up gas reserves, and drill extensive horizontal holes to suck in gas from much wider areas. Kate Mishkin, ProPublica, "Court to Big Fracking Company: Trespassing Still Exists — Even For You," 6 June 2019 LaFarge’s mine is about 200 to 400 feet underground and is mainly used to produce limestone and dolomite aggregates for construction uses. Steve Lord, Aurora Beacon-News, "Aurora says new lime disposal deal would save city millions of dollars," 6 June 2019 Johnson pointed out the tunnels where the now-underground Park River joins the Connecticut River. Annie Gentile, courant.com, "Historical Society Celebrates Trails Day," 6 June 2019 An excess-flow valve is installed on the service line underground, near the line’s intersection with the gas main. Nathaniel Penn, Popular Mechanics, "The Day the Town Blew Up," 3 June 2019 The underground club scene, as a result, is still in its infancy. Vogue, "This All-Female DJ Collective Wants to Empower the Women of Shanghai’s Nocturnal World," 15 May 2019 Its roots are elsewhere, in the atmospheric, almost literary horror produced by Britain’s Hammer Films in the 1950s and 1960s, and in the gritty, unsettling docu-realism of the New York underground cinema scene. Noel Murray, The Verge, "Silent Night, Bloody Night is the perfect streaming slasher for Halloween fans," 20 Oct. 2018 Pose has introduced viewers to a roster of diverse characters, including a number of transgender characters, homeless youth, and other colorful personalities who live, thrive, and struggle in New York City's underground ball scene in 1987. Terrence Chappell, Teen Vogue, ""Pose" Takes Place in the 1980s, But Conversations About LGBTQ Homelessness and AIDS Are Still So Important," 15 July 2018 Manhattan houses 35,000 underground and 47,000 overhead transformers for its 10 million residents, and of those 82,000, about 35 fail every year, McGee says. Cassie Rodenberg, Popular Mechanics, "How Transformers Can Explode," 28 Dec. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'underground.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of underground

Adverb

14th century, in the meaning defined at sense 1

Noun

1594, in the meaning defined at sense 1

Adjective

1601, in the meaning defined at sense 1

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Statistics for underground

Last Updated

13 Jun 2019

Look-up Popularity

Time Traveler for underground

The first known use of underground was in the 14th century

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More Definitions for underground

underground

adverb

English Language Learners Definition of underground

 (Entry 1 of 3)

: below the surface of the earth
: in or into a place that is hidden or secret : out of the view of the public

underground

noun

English Language Learners Definition of underground (Entry 2 of 3)

British : a system of trains that run below the ground in a large city
: a group of people who secretly work to oppose or overthrow a government

underground

adjective

English Language Learners Definition of underground (Entry 3 of 3)

: located or occurring below the surface of the earth
: secret and usually illegal
: of, relating to, or produced in a social and artistic world that is different and separate from the main part of society

underground

adverb
un·​der·​ground | \ ˌən-dər-ˈgrau̇nd How to pronounce underground (audio) \

Kids Definition of underground

 (Entry 1 of 3)

1 : below the surface of the earth
2 : in or into hiding or secret operation The rebels went underground.

underground

noun
un·​der·​ground | \ ˈən-dər-ˌgrau̇nd How to pronounce underground (audio) \

Kids Definition of underground (Entry 2 of 3)

1 : subway
2 : a secret political movement or group

underground

adjective
un·​der·​ground | \ ˈən-dər-ˌgrau̇nd How to pronounce underground (audio) \

Kids Definition of underground (Entry 3 of 3)

1 : located under the surface of the ground underground pipes
2 : done or happening secretly an underground revolt

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Comments on underground

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