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

Keep scrolling for more

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.
See More
Recent Examples on the Web: Adverb The Haunted Mine Drop, which opened in July 2017, is billed as the first drop ride to go underground, plunging riders 110 feet (33 meters) inside of Iron Mountain. orlandosentinel.com, 7 Sep. 2021 The Haunted Mine Drop, which opened in July 2017, is billed as the first drop ride to go underground, plunging riders 110 feet inside of Iron Mountain. Jordan Mendoza, USA TODAY, 6 Sep. 2021 The Haunted Mine Drop is billed as the world's first drop ride to go underground, according to the park website. Amanda Jackson, CNN, 6 Sep. 2021 When the neighbors complain and police take notice, the brothels go underground and move to another location, popping up in new places owned by various limited liability corporations that conceal their ownership. BostonGlobe.com, 27 July 2021 With medics driven underground amid a global pandemic, the country's already fragile healthcare system is crumbling. Star Tribune, 6 July 2021 Detecting bitcoin transfers is difficult, and would ultimately end up re-victimizing targets and discourage them from reporting as the communication is driven underground. Edward Segal, Forbes, 8 June 2021 Nidhi Rana, 18, and Ayush Rana, 21, were last seen Wednesday evening when their car began floating toward a spot where the water flows underground toward the Passaic River. BostonGlobe.com, 5 Sep. 2021 The company proposes to use solution mining — wells not unlike typical oil and gas fracking wells, but that would inject brine water thousands of feet underground to dissolve potash, bring it to the surface, and then dry and reconstitute it. Keith Matheny, Detroit Free Press, 5 Sep. 2021 Recent Examples on the Web: Noun North-central Lower Michigan may have a reserve of potash, an important agricultural fertilizer, worth more than $65 billion, about a mile-and-a-half underground. Keith Matheny, Detroit Free Press, 5 Sep. 2021 Footage from the chaos underground circulated widely on messaging app WeChat, a key mode of communication in the country. Washington Post, 21 July 2021 Tarnas and his colleagues also evaluated the potential richness of life in the Martian underground and found that as many as a million microbes could exist in a kilogram of rock. Nikk Ogasa, Scientific American, 19 July 2021 But its members are mingling with the hacktivist underground, which includes people engaging in potentially criminal behavior. Jacob Silverman, The New Republic, 18 Aug. 2021 But while purists might see the prospect of mainstream acceptance as a threat to this once-underground culture, Chopper welcomed the development. Dan Campisi, CNN, 23 July 2021 In Anyang, another city in Henan, officials on Thursday halted all public transport, vacated underground garages, and told residents not to leave their homes unless absolutely necessary. Washington Post, 22 July 2021 Fans had been arriving at the Wembley Park underground station all day, gathering in ever greater numbers in the shadow of the stadium. New York Times, 16 July 2021 San Diego International Airport captures, stores, and reuses all the rain that falls on the top deck of its 7.6-acre parking plaza and has a 3-million-gallon underground cistern to capture stormwater from airport property north of runway. NBC News, 16 June 2021 Recent Examples on the Web: Adjective However, for about a month, crews have been busy tearing up parking lot asphalt and removing old underground pipes to prepare for the development's new buildings. Jc Reindl, Detroit Free Press, 11 Sep. 2021 This allowed the farmer to save on expensive infrastructure costs such as underground pipes and micro-irrigation technology and made sense when water was abundant and cheap. Nav Athwal, Forbes, 30 Aug. 2021 Green said if forecasts of up to 20 inches of rain prove true, the city's underfunded and neglected network of pumps, underground pipes and surface canals likely won't be able to keep up. David Aaro, Fox News, 30 Aug. 2021 While water may not penetrate levees, Green said if forecasts of up to 20 inches of rain prove true, the city's underfunded and neglected network of pumps, underground pipes and surface canals likely won't be able to keep up. Compiled Democrat-gazette Staff From Wire Reports, Arkansas Online, 30 Aug. 2021 But if forecasts of up to 20 inches (50 centimeters) of rain come true, the city's underfunded and neglected network of pumps, underground pipes and surface canals likely can't keep up, Green said. Kevin Mcgill And Jay Reeves, The Christian Science Monitor, 29 Aug. 2021 Some will go to infrastructure, including replacing deteriorated underground corrugated metal pipes at Monte Mar Drain Channel and the West Vista Way Drain Channel. Laura Groch, San Diego Union-Tribune, 29 Aug. 2021 While water may not penetrate levees, Green said if forecasts of up to 20 inches (50 centimeters) of rain prove true, the city's underfunded and neglected network of pumps, underground pipes and surface canals likely won't be able to keep up. Kevin Mcgill And Jay Reeves, Chron, 29 Aug. 2021 Enter drainage tile systems: a network of underground pipes to help carry away excess water. Sarah Bowman, The Indianapolis Star, 12 Aug. 2021

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.

See More

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

Keep scrolling for more

Learn More About underground

Time Traveler for underground

Time Traveler

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

See more words from the same century

Dictionary Entries Near underground

undergroom

underground

undergrounder

See More Nearby Entries 

Statistics for underground

Last Updated

19 Sep 2021

Cite this Entry

“Underground.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/underground. Accessed 23 Sep. 2021.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon

Keep scrolling for more

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 : subway
: 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

More from Merriam-Webster on underground

Nglish: Translation of underground for Spanish Speakers

Britannica English: Translation of underground for Arabic Speakers

Britannica.com: Encyclopedia article about underground

WORD OF THE DAY

Test Your Vocabulary

Farm Idioms Quiz

  • cow coming home
  • What does 'poke' refer to in the expression 'pig in a poke'?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
 AlphaBear 2

Spell words. Make bears.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!