underground

1 of 3

adverb

un·​der·​ground ˌən-dər-ˈgrau̇nd How to pronounce underground (audio)
1
: beneath the surface of the earth
2
: in or into hiding or secret operation

underground

2 of 3

noun

1
: a subterranean space or channel
2
: an underground city railway system
3
a
: 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

3 of 3

adjective

un·​der·​ground ˈən-dər-ˌgrau̇nd How to pronounce underground (audio)
1
: being, growing, operating, or situated below the surface of the ground
2
: conducted by secret means
3
a
: existing outside the establishment
an underground literary reputation
b
: existing outside the purview of tax collectors or statisticians
the underground economy
4
a
: 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

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.
Recent Examples on the Web
Adverb
Instead, the buildings will rely on a cooling system that uses water pulled from underground. Catherine Porter, New York Times, 16 Mar. 2024 Prolonged droughts adversely affect costs if suppliers need to buy a more expensive water supply, pump water from deeper underground or add treatment processes to clean degraded supplies, researchers with the Pacific Institute and the organization Dig Deep said in a recent report. Anthony De Leon, Los Angeles Times, 12 Mar. 2024 The companies also are spending heavily to harden their equipment, replacing old wooden power poles, covering some power lines with a protective sheath while burying others underground. David R. Baker, Fortune, 7 Mar. 2024 The same thing happens when oil and gas are extracted from underground. Cnn.com, The Mercury News, 7 Mar. 2024 These North American amphibians, which spend most of their time hibernating underground, dislike being threatened. Popular Science, 6 Mar. 2024 See it → 3,500-year-old shipwreck — one of world's oldest — sank carrying items in hot demand Between about 30 and 40 inches underground, there was an even older structure, officials said. Moira Ritter, Miami Herald, 22 Feb. 2024 She’d been assigned a job at a coal mine, like her father and most people in their village near the Chinese border – but the teenager didn’t want to spend her life doing hard labor, deep underground. Jessie Yeung, CNN, 8 Mar. 2024 The second-largest city in Ukraine has been building schools underground and holding classes in subway stations doubling as bomb shelters. Suzanne Nuyen, NPR, 23 Feb. 2024
Noun
Farrell gives a classic gangster monologue throughout the trailer, which slowly ramps up the violence and gunfights in Gotham City’s seedy underground. Caroline Brew, Variety, 22 Mar. 2024 Rather than targeting big corporations, the hackers in India’s underground are routinely paid to access personal email accounts, whether by a wife spying on her husband’s financial affairs or a blackmail victim searching for a way out of their predicament. Chris Wheatley, Longreads, 12 Mar. 2024 Of course, one of the main challenges remains simply digging deep enough into the Earth’s crust to tap the staggering amount of geothermal energy underground. IEEE Spectrum, 12 Mar. 2024 These actions have often been accompanied by sanctions and indictments for key members of the cybercrime underground. Matt Burgess, WIRED, 20 Feb. 2024 It is seen most clearly in rising rap, where the online underground encompasses a diffuse sprawl of scenes and standards that share a cracked sensibility. Kieran Press-Reynolds, Pitchfork, 19 Jan. 2024 From letter bombs to exploding mobile phones to drone strikes, targeting enemies for assassination has long been part of Israel’s playbook, dating back to the Zionist underground movement before the country’s founding. Keir Simmons, NBC News, 9 Jan. 2024 They soon get involved in a mystery surrounding the Woods, a secret underground facility at Godolkin were young supes are held captive and forced into harmful experiments. Nick Romano, EW.com, 6 Oct. 2023 Deep underground, a construction crew is hard at work. Ricky Carioti, Washington Post, 7 July 2023
Adjective
Monumental also projected that its 2,200 underground spaces would be filled before fans park elsewhere, despite there being more affordable lots that exist nearby. Jonathan O'Connell, Washington Post, 14 Mar. 2024 This will help geologists understand how the eclipse may affect underground drinking water reservoirs. Karl Schneider, The Indianapolis Star, 13 Mar. 2024 The group has criticized plans Habeck, a member of the environmentalist Green party, announced last month to enable underground carbon storage at offshore sites. Geir Moulson, Quartz, 12 Mar. 2024 Playing a character known as Kid, who works as an underground fight-club boxer who gets paid each night to put on a rubber gorilla mask and get beaten to a pulp, Patel creates a hero who is very much not some invincible combat superstar. Owen Gleiberman, Variety, 12 Mar. 2024 Now a drifter scrounging by on an underground fight circuit, Dalton is offered a job by Frankie (Williams) to work as a bouncer at her bar in the Florida Keys. Mark Olsen, Los Angeles Times, 9 Mar. 2024 Monitoring of individual underground reserves is patchy at best. Fred Pearce, WIRED, 9 Mar. 2024 Cave churches, underground cities, and homes carved into the rocks work to create a whimsical aura usually reserved for the fictional realm. Claudia Fisher, Travel + Leisure, 2 Mar. 2024 In California and many other parts of the world, traditional water sources — including underground aquifers and fresh water from rivers, streams and snowmelt — are becoming less reliable. Hayley Smith, Los Angeles Times, 1 Mar. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'underground.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

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

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

Dictionary Entries Near underground

Cite this Entry

“Underground.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/underground. Accessed 28 Mar. 2024.

Kids Definition

underground

1 of 3 adverb
un·​der·​ground ˌən-dər-ˈgrau̇nd How to pronounce underground (audio)
1
: below the surface of the ground
an underground passage
2
: in or into hiding or secret operation
the political party went underground

underground

2 of 3 noun
un·​der·​ground
ˈən-dər-ˌgrau̇nd
1
: a space under the surface of the ground
especially : subway sense 2
2
: a secret political group
especially : an organized body working in secret to overthrow a government or an occupying power

underground

3 of 3 adjective
un·​der·​ground ˈən-dər-ˌgrau̇nd How to pronounce underground (audio)
1
: being, growing, operating, or located below the surface of the ground
an underground stream
2
: conducted secretly

More from Merriam-Webster on underground

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