underground

adverb
un·​der·​ground | \ˌən-dər-ˈgrau̇nd \

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 \

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 \

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

Euronews was shown one film dedicated to heavy metal - featuring sound equipment being buried underground! Lawrence Elizabeth Knox, Houston Chronicle, "A ‘Cosmic Evening’ with tomorrow’s stars at Texas Music Festival," 6 June 2018 Hardy microbes may live deep underground in such places, but there were no monsters, no maidens in need of saving, no masterminds devising evil plans. Steve Donoghue, The Christian Science Monitor, "3 books about planets," 18 May 2018 The Middleburg hotel could break ground as soon as August to jumpstart required underground utility work. Beth Mlady, cleveland.com, "Middleburg Planning Commission approves site plans for new Tru by Hilton hotel," 11 May 2018 In addition to the meteor crash, Epic transformed its map in subtle but powerful ways, adding new structures, secret underground lairs, and other goodies in service to its new superhero theme. Nick Statt, The Verge, "Fortnite is the biggest game on the planet right now because it’s a living, breathing world," 6 May 2018 Freeport plans to finish mining the available aboveground Grasberg resources this year before extracting metal underground in the future, a main reason analysts are waiting to see what form a possible deal with the government takes. Amrith Ramkumar, WSJ, "Freeport Is Worst Performer in S&P 500 as Indonesia Troubles Pound Shares," 24 Apr. 2018 The snakes spend much of their time underground in the burrows of their pocket gopher prey. Sara Sneath, NOLA.com, "Louisiana constrictor snake granted protection under the Endangered Species Act," 6 Apr. 2018 Everyone concedes there are more water rights on paper than there is water stored underground in Pinal County. Dustin Gardiner, azcentral, "Arizona aquifers are in trouble, but lawmakers want fewer rules for pumping groundwater," 4 Apr. 2018 Each one consists of a rubber tub buried underground containing sensors that pick up shaking. Meghan Bartels, Newsweek, "When 'The Big One' Strikes, New Earthquake Warning System Could Reduce Deaths," 13 Mar. 2018

Recent Examples on the Web: Noun

Is this a different underground lab than the one Bernard and Elsie stumbled into a few episodes back? William Lee, chicagotribune.com, "‘Westworld’ Episode 10 recap: 5 things to know about ‘The Passenger’ and Season 2's finale," 24 June 2018 All are on display in Florida’s only cave tour, a leisurely 45- to 60-minute-trip into the dark, and extremely warm by the way, multi-room underground. Richard Tribou, OrlandoSentinel.com, "Explore Florida's Jackson County: Dare to dwell deep underground," 6 May 2018 There’s a $4 billion budget estimate to add 1.3 miles of underground tracks from Mission Bay up Second Street into a concrete shell that now sits empty beneath the facility. John King, SFChronicle.com, "S.F.’s long-awaited Salesforce Transit Center sets opening date for Aug. 12," 10 July 2018 The season finale begins with the show's main characters converging on that enigmatic underground building. Sandra Upson, WIRED, "Westworld Recap, Season 2 Episode 10: What Is Real?," 25 June 2018 In a large underground room beneath the IAEA's office tower, banks of TV monitors flicker with live images from inside Iran's sole functioning uranium enrichment plant. Author: Joby Warrick, Anchorage Daily News, "Muzzled watchdog: How killing the nuclear deal could make it easier for Iran to pursue the bomb in secret," 8 May 2018 But for reasons both humorous and poignant, Grump has never fit in underground with the others. The Christian Science Monitor, "4 delightful new books for middle-grade readers," 7 June 2018 And the record of the Polish government-in-exile and underground is much more complex and compromised than the statement allows. Jeet Heer, The New Republic, "Israeli historian accuses Benjamin Netanyahu of whitewashing Polish complicity in the Holocaust.," 5 July 2018 Webster and his colleagues suspect that the methane comes from deep underground, and temperature swings on Mars’s surface throttle its flow upward. National Geographic, "Building Blocks of Life Found on Mars," 7 June 2018

Recent Examples on the Web: Adjective

Leto, set in the days just before the dawn of Perestroika, is a movie musical about young rock musicians in Leningrad’s underground scene trying to make their own music while poring over everything from punk to folk rock from the West. Alissa Wilkinson, Vox, "This year’s Cannes Film Festival was a plea against complacency," 18 May 2018 Punk had morphed into hardcore and a whole new underground scene was taking root. John Petkovic, cleveland.com, "Punk pioneer Tommy Strange returns to Ohio with band His Name is Joe," 4 May 2018 Others said that dust can seep into underground shelters, causing choking and other symptoms associated with chemical attacks. Time, "Investigators Were Kept from Entering the Site of the Alleged Chemical Weapons Attack in Syria," 18 Apr. 2018 Residents of eastern Ghouta are sheltering in schools, mosques, basements, and makeshift underground shelters that have sometimes collapsed over them during the shelling. Scott Peterson, The Christian Science Monitor, "Why Syrians in besieged eastern Ghouta refuse to leave," 5 Mar. 2018 In the hunt, scientists have erected detectors in a South Dakota cavern a mile underground, at the bottom of Lake Baikal in Siberia, under a mountain in Japan, and on the floor of the Mediterranean Sea. Robert Lee Hotz, WSJ, "Scientists Track Neutrinos Through Ice to Their Source in the Cosmos," 12 July 2018 Above these galleries, but still underground, is an atrium, with an adjoining cafe and a theater named for Oprah Winfrey, who is also the subject of a new exhibition at the museum. Blair Kamin, chicagotribune.com, "The national African-American museum still stirs the soul — and drops hints of what to expect at the Obama Presidential Center," 11 July 2018 This tour has always done its best to represent a wide variety of alternative sounds, and this year had two stages devoted to bands on the heavier side of the underground, from MyChildren MyBride to Nekrogoblikon and Senses Fail. Ed Masley, azcentral, "Vans Warped Tour says goodbye to Phoenix in its final summer on the road," 29 June 2018 The bitcoin community is known for its underground, libertarian bent. Emily Stewart, Vox, "Steve Bannon’s post-Breitbart project is bitcoin because of course it is," 14 June 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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Last Updated

17 Oct 2018

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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)

: a system of trains that run below the ground in a large city

the underground : 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 \

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 \

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 \

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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