1
as in clandestine
undertaken or done so as to escape being observed or known by others
an underground operation to smuggle ancient artifacts out of the country
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Antonyms & Near Antonyms
2
as in subterranean
being, situated, or operating beneath the surface of the earth
an underground shopping mall that is part of the city's subway system
Synonyms & Similar Words
Antonyms & Near Antonyms
as in resistance
a secret organization in a conquered country fighting against enemy forces
joined the underground while still a teenager
Synonyms & Similar Words
as in undercover
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Antonyms & Near Antonyms
Example Sentences
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Recent Examples of underground
Paul Lipman, Forbes.com, 4 Apr. 2025
Despite the Southland’s dry turn, the Metropolitan Water District of Southern California reports a record amount of water banked in reservoirs and underground storage areas.
—Ryan Fonseca, Los Angeles Times, 4 Apr. 2025
Susan Bard, Health, 18 Mar. 2025
The property would include 36 parking spaces — 22 surface-level and 14 underground.
—Joe Marusak, Charlotte Observer, 17 Mar. 2025
Nancy Walecki, The Atlantic, 18 Mar. 2025
They must be concealed and mobile; or they must be put underground and defended with antimissile systems such as Patriot and Aegis Ashore that the United States has been transferring to Israel, Poland, and Ukraine.
—Stephen Peter Rosen, Foreign Affairs, 14 Mar. 2025
See All Example Sentences for underground
Adjective
For example, ultra-low frequency (ULF) and very-low frequency (VLF) radio—used in fields including submarine and underground communications—require antennas that can span tens to hundreds of meters in size.
—Paul Lipman, Forbes.com, 4 Apr. 2025
Despite the Southland’s dry turn, the Metropolitan Water District of Southern California reports a record amount of water banked in reservoirs and underground storage areas.
—Ryan Fonseca, Los Angeles Times, 4 Apr. 2025
Noun
Salt water from the ocean or underground is rich in minerals and may provide the body with magnesium.
—Susan Bard, Health, 18 Mar. 2025
The property would include 36 parking spaces — 22 surface-level and 14 underground.
—Joe Marusak, Charlotte Observer, 17 Mar. 2025
Adverb
And the Los Angeles Department of Water and Power recently pledged to put all of the Palisades’ power lines underground.
—Nancy Walecki, The Atlantic, 18 Mar. 2025
They must be concealed and mobile; or they must be put underground and defended with antimissile systems such as Patriot and Aegis Ashore that the United States has been transferring to Israel, Poland, and Ukraine.
—Stephen Peter Rosen, Foreign Affairs, 14 Mar. 2025
See All Example Sentences for underground
Recent Examples of Synonyms for underground
Adjective
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Taking over a century-old garden house hidden within Shanghai’s storied alleys, Samuel Gui Yang softly partitioned the space, seducing the audience yet making every one of them a clandestine voyeur.—
Tianwei Zhang,
Footwear News,
1 Apr. 2025
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In a display of gallows humor at the sloppiness of the leaders’ theoretically clandestine communication, people online quickly turned those symbols into memes, and renamed their own chats Houthi PC small group.—
Kyle Chayka,
The New Yorker,
26 Mar. 2025
Adjective
-
Sure, the cost of a tunnel 60 feet underground with elevators, escalators and stairs leading to a subterranean platform with ventilation shafts, lighting and security is exorbitant.—
Sun Sentinel Editorial Board,
Sun Sentinel,
5 Apr. 2025
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Many years later, my subterranean tours, including Kartchner Caverns in Arizona and Luray Caverns in Virginia, became trip highlights.—
Pat Tompkins,
AFAR Media,
4 Apr. 2025
Noun
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Both Ward and Davis recognize that the truck will attract some resistance from diehard traditionalists.—
Michael Van Runkle,
Robb Report,
2 Apr. 2025
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But a longer-term offensive in Gaza could also draw stiff resistance from the Israeli public, a majority of which has been clamoring for a hostage release deal instead of a return to war.—
Eugenia Yosef,
CNN Money,
2 Apr. 2025
Adjective
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Alan Ritchson says Reacher is the American James Bond Reacher works with DEA agents Susan Duffy (Cassidy) and Guillermo Villanueva (Roberto Montesinos) to go undercover in the rug-importing front, which is led by businessman Zachary Beck (Hall).—
Randall Colburn,
EW.com,
1 Apr. 2025
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To investigate further, the DEA had five undercover officers visit his clinic to see whether Hollington would prescribe them medications without legit medical reasons between February and July 2022, prosecutors said.—
Julia Marnin,
Miami Herald,
31 Mar. 2025
Adjective
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Then Gungnir covert sniper rifle seems like a bargain, relatively speaking, at just $12,867.—
Davey Winder,
Forbes.com,
28 Mar. 2025
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In the letter, Grassley wrote that the records would help shine a light on the Nazi planning of the covert escape routes.—
Michael Dorgan,
FOXNews.com,
27 Mar. 2025
Adjective
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Elsewhere is a cozy study for getting some work done, while both a private garden and a rooftop terrace serve as ideal spots for dining alfresco when the London weather decides to cooperate.—
Tori Latham,
Robb Report,
8 Apr. 2025
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Rural communities could be unequally impacted Unlike the postal service, private companies do not have the same service obligations requiring delivery to rural or sparsely-populated areas – even at a loss.—
Eric Lagatta,
USA Today,
7 Apr. 2025
Cite this Entry
“Underground.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/underground. Accessed 10 Apr. 2025.
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