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

The remaining 239 people who were underground when the tremor occurred escaped to the surface safely. Jordan Blum, Houston Chronicle, "Major methane study complicates plans of oil and gas industry," 21 June 2018 Nick Jonas knows the most efficient way to get around in New York City is underground. Lindsay Kimble, PEOPLE.com, "Nick Jonas Took the Subway to the Met Gala While Wearing Dolce & Gabbana," 8 May 2018 Guests have access to the private white sand beaches, luscious gardens, three pools — one is underground — and a rooftop with 360-degree jungle views. Jenna Milliner-waddell, ELLE Decor, "'Narcos' Fans, Take Note: You Can Stay In A Mexican Mansion Once Owned By Pablo Escobar," 25 July 2017 Hundreds of civilians were killed and the offensive drove most people to shelter underground. Raja Abdulrahim, WSJ, "Syria’s Former Rebel Strongholds Endure as Assad Regime Reasserts Control," 12 July 2018 Instead of recriminations over his role leading the children into the cave, Thai social media portrayed him as a hero for looking after the children underground. George Styllis, latimes.com, "From mission impossible to mission accomplished: Thailand rejoices as last boys rescued from cave," 11 July 2018 In 2010, Man United hosted a group of miners from Chile who spent almost 10 weeks underground before being rescued. Graham Dunbar, The Seattle Times, "Rescued Thai soccer team unable to attend World Cup final," 10 July 2018 Their water supply is often drained off or broken underground by decades of coal mining. Jedediah Purdy, The New Republic, "The Remaking of Class," 27 June 2018 They were located by a British diving team late Monday after nearly 10 days underground, setting off a challenging operation to take them out safely. Wilawan Watcharasakwet And Phred Dvorak, WSJ, "Thailand Cave Rescue: Former Thai Navy SEAL Dies After Diving Operation," 6 July 2018

Recent Examples on the Web: Noun

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 Critics of the project say the massive underground tunnels would do more harm to the Delta, not less. Dale Kasler, sacbee, "Southern California water agency agrees to spend $11 billion on Delta tunnels - again," 10 July 2018 Groves of hardy bristlecone pines — the world’s longest-living tree — flourish above 9,000 feet, while caves riddle the underground. David Swanson, latimes.com, "National parks where you can find solitude in summer," 1 July 2018 Because geologic processes move material from underground to the surface, the reverse may also be happening, transporting surface materials highly oxidized by Jupiter’s harsh radiation down through the ice. Ramin Skibba, Scientific American, "Decades-Old Data Unveils Plumes Spewing from Europa," 14 May 2018 The underground's absolute A-list party brand is coming in for a landing with some seriously funky bass brawlers on Aug. 2. Kat Bein, Billboard, "DJ Snake, Virtual Self & More to Headline HARD Red Rocks 2018," 9 Apr. 2018

Recent Examples on the Web: Adjective

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 The church proposed building a massive apartment complex with 176 units and more than 500 underground parking spaces. Maria L. La Ganga, idahostatesman, "A Boise church lost a bitter fight to develop this lot. Now it may build housing there," 13 June 2018 The company plans to transport passengers between O’Hare and Block 37 in the Loop in approximately 12 minutes each way by utilizing electric vehicles that run through new twin underground tunnels. Ben Joravsky, Chicago Reader, "Politics / Transportation Another whopper from Rahm: express service to O'Hare that won’t cost the public," 18 June 2018 But Chicago bondholders are also voicing cautious optimism that the project -- which will use electric vehicles to transport passengers through new underground tunnels -- is an economic win for the nation’s third-largest city. Elizabeth Campbell, Bloomberg.com, "Hounded by Woes, Chicago Sees Musk's Train as Win for Its Economy," 14 June 2018 Replacing the 2-mile Alaskan Way Viaduct with an underground tunnel has taken seven years, and cost Seattle $2 billion and counting. Aarian Marshall, WIRED, "Elon Musk’s Boring Company Wins a Big Boring Contract in Chicago," 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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Phrases Related to underground

go underground

the underground

Statistics for underground

Last Updated

19 Sep 2018

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)

: 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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Comments on underground

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