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
For this project, companies will need to capture, compress and transport CO2 underground — a process that requires a lot of energy and potentially could lead to more emissions. Tony Briscoe, Los Angeles Times, 22 Oct. 2024 The Israeli military says the bunker contains living quarters and amenities for extended stays, equipment for commanding Hezbollah members from underground, and a vast fortune. Timothy Nerozzi, Washington Examiner - Political News and Conservative Analysis About Congress, the President, and the Federal Government, 22 Oct. 2024
Noun
The company has amassed a war chest to lead the hunt for naturally-occurring hydrogen underground. Katie Fehrenbacher, Axios, 15 Oct. 2024 Instead, Weilerstein seems to serve as part of the weird Mayan underground, with its mysterious gods and beasts. Mark Swed, Los Angeles Times, 12 Oct. 2024
Adjective
Hezbollah leader Nasrallah was killed in an Israeli strike on his underground headquarters in Beirut in September. Helen Regan, CNN, 26 Oct. 2024 This underground marvel spirals downwards, with walls lined with some of the world’s rarest wines, creating an enchanting display of history and luxury. Rooksana Hossenally, Forbes, 26 Oct. 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 31 Oct. 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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