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

Avondale recently moved utility lines underground and this month started a project that will repave Dysart Road, improve landscaping and add lighting for pedestrians. Parker Leavitt, azcentral, "Readers' picks: Worst West Valley eyesores," 16 Feb. 2016 Yet even as private bicycles move underground, new invaders are clogging Dutch pavements. The Economist, "The Dutch underground bicycle-park arms race," 12 July 2018 In India, severe restrictions on how political parties can raise money have driven campaign finance underground and fostered a culture of corruption and kickbacks, experts say. Simon Denyer, Washington Post, "Mongolian democracy has a familiar ailment, and it’s all about money," 26 June 2018 The bare-knuckle fights that all but disappeared from public view in the USA after 1889 simply moved underground, according to Gunn, who sported an unofficial record of 71-0 before the festivities moved into a legitimate venue Saturday. Josh Peter, USA TODAY, "Fight club: Legalized bare-knuckle boxing may be next big show in ring," 4 June 2018 Black people are only fit to live underground like groveling goblins. Ryan Gaydos, Fox News, "Twitter apologizes after conservative commentator Candace Owens was briefly locked out of her account," 6 Aug. 2018 Britain has been enjoying a particularly long spell of warm weather, which probably triggered the ants to emerge from underground earlier than in recent years. Jennifer Hassan, Washington Post, "For Americans, it’s the Fourth of July. For Brits, it’s Flying Ant Day.," 4 July 2018 While the Punggye-ri facility is made up of tunnels deep underground and was believed to be heavily fortified, Iha-ri was composed of facilities that were relatively to take apart. Joshua Berlinger, CNN, "North Korea razes missile test site, monitoring group 38 North says," 6 June 2018 Because filmmakers have to submit screenplays to the government for approval before shooting, some went underground and made movies in their homes or cars, Mr. Naficy said. Farah Nayeri, New York Times, "Fighting for the Palme d’Or, and the Right to Fly to Cannes," 9 May 2018

Recent Examples on the Web: Noun

They are entered via a series of underground poured-concrete steps, and confining even for a five-foot-tall person like me. Alexandra Lange, Curbed, "Gateway to what?," 28 June 2018 Two European firms are backing an ambitious $2.5 billion project to carry renewable electricity underground through the American heartland. Russell Gold, WSJ, "‘Extension Cord’ to Carry Green Power From Midwest to East," 10 Mar. 2019 Would the government of the U.S. leave shale oil underground? WSJ, "What Could Go Wrong With Climate Change Investing," 13 Dec. 2018 This past summer, the iconic Hotel Jerome in Aspen unveiled a conversion of the 140-year-old Aspen Times building into an events space with a sultry new underground bar, Bad Harriet, named for the hotel’s original developer. Alex Postman, Condé Nast Traveler, "If You're Skiing the Rockies This Winter, Read This First," 4 Dec. 2018 Like the kilogram standards, the Kibble balance is housed deep underground at NIST. Brian Resnick, Vox, "The world is about to redefine the kilogram," 15 Nov. 2018 The single-line, 15.5-mile heavy rail system runs above ground from Owings Mills to Mondawmin and underground between Mondawmin and Johns Hopkins Hospital. Colin Campbell, baltimoresun.com, "Transit union warned of unsafe Baltimore Metro tracks for several years," 22 June 2018 The pipeline from China to the U.S. is connected by an online marketplace that is moving commerce deeper underground on the dark web, where drug purchases can be made with anonymity. Kristina Davis, sandiegouniontribune.com, "Fentanyl has taken over America's drug market. Where is it coming from?," 17 June 2018 But even before the eruption, magma shifting around underground was already causing quakes, CNN meteorologist Judson Jones said. Holly Yan, CNN, "Here's what Hawaii's volcano eruption looks like -- by the numbers," 7 May 2018

Recent Examples on the Web: Adjective

But by his teens, Jeter’s older cousins took him under their wing and introduced him to New Haven’s underground economy. Matthew Ormseth, courant.com, "Paroled After Two Decades In Prison, James Jeter Will Attend Trinity College This Fall," 8 July 2018 The walkway includes an underground heating system that will prevent ice and snow accumulation in the winter months, improving safety and reducing salt and snow removal costs. Staff Report, Post-Tribune, "Community news," 30 May 2018 Just hours before, two dozen outside reporters had watched from a remote location as Pyongyang claimed to demolish its underground nuclear test site. Heather Hurlburt, Daily Intelligencer, "What Happens When You Treat Nuclear Diplomacy Like a Reality TV Show," 24 May 2018 For the rest of the year, the only sign of life is the odd patch of bright green reeds, fed by underground water. Mary Holland, Condé Nast Traveler, "Why Your Next Safari Should Be in Namibia," 6 Nov. 2018 Residents became alarmed about water contamination after recent media reports of traces of firefighting chemicals were found in the underground water at the Air Force base in 2014 and 2017. Martin E. Comas, OrlandoSentinel.com, "Brevard County schools to test drinking water at 13 campuses for chemical contamination," 3 July 2018 The project still needs a permit from the State Water Commission to use underground water for the refinery. Washington Post, "North Dakota OKs refinery construction near national park," 13 June 2018 The system’s efficiency is boosted by a geothermal heat pump that sheds excess heat or cold through a circuit of underground pipes. National Geographic, "From Historic to Cutting Edge: Revitalizing Iconic Buildings," 25 May 2018 So the project does not cover the current shortfall, which is made up by underground water. The Economist, "China has built the world’s largest water-diversion project," 5 Apr. 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

18 Apr 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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