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
Case in point: the hot springs flowing underground are fed into the plunge pools in every room, and the spa treatments are just as locally inspired and often call on the healing and skincare powers of coffee, chocolate, and volcanic mud. Chadner Navarro, Vogue, 15 June 2024 East of El Paso, in an arid region called the Forgotten Reach, the Rio Grande, fed by no major tributaries, largely disappears underground for almost two hundred miles. Rachel Monroe, The New Yorker, 13 June 2024
Noun
The company also highlighted that the mine’s power supply will come from renewable energy with a future all-electric underground mining fleet. Sarah Lapidus, The Arizona Republic, 22 May 2024 Unlike rivers and lakes, aquifers hold freshwater underground, and that freshwater is then pumped out of the aquifers for irrigation and drinking. Devika Rao, theweek, 1 Feb. 2024
Adjective
Pastor Troy’s aggressive performance and confrontational lyrics address themes of street life and regional pride, resonating with Atlanta’s underground rap scene. Walaa Elsiddig, Billboard, 17 June 2024 But when everything goes wrong, the duo must evade capture not only from the police but also from corrupt bureaucrats and underground crime lords. Jack Dunn, Variety, 13 June 2024 See all Example Sentences for underground 

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 30 Jun. 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

Last Updated: - Updated example sentences
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