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
Synonyms & Similar Words
Relevance
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
Related Words
Dissimilar Words
Example Sentences
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Recent Examples of underground
Thomas Gounley, Denver Post, 6 Feb. 2026
New this time around will be Taste of Tokyo, a Japanese car showcase with the vibe of an underground car meet.
—Rod Stafford Hagwood, Sun Sentinel, 4 Feb. 2026
Angel Saunders, PEOPLE, 6 Jan. 2026
The seductive tale set in the nightclub underground of Weimar-era Berlin swept the Tony Awards the following year, earning Grey a trophy.
—Ryan Coleman, Entertainment Weekly, 22 Dec. 2025
Ashley Carnahan, FOXNews.com, 3 Feb. 2026
Russian attacks on civilians in Kherson, in southern Ukraine, have forced important aspects of life to go underground, offering a vision of a postapocalyptic future.
—Berry Wang Mauricio Lima David Marchese W.j. Hennigan, New York Times, 2 Feb. 2026
See All Example Sentences for underground
Adjective
Two levels of underground parking are planned.
—Thomas Gounley, Denver Post, 6 Feb. 2026
New this time around will be Taste of Tokyo, a Japanese car showcase with the vibe of an underground car meet.
—Rod Stafford Hagwood, Sun Sentinel, 4 Feb. 2026
Noun
The same streets, the same underground.
—Angel Saunders, PEOPLE, 6 Jan. 2026
The seductive tale set in the nightclub underground of Weimar-era Berlin swept the Tony Awards the following year, earning Grey a trophy.
—Ryan Coleman, Entertainment Weekly, 22 Dec. 2025
Adverb
Residents took to subway and metro stations on Monday to hide underground as air raid alerts sounded throughout the night.
—Ashley Carnahan, FOXNews.com, 3 Feb. 2026
Russian attacks on civilians in Kherson, in southern Ukraine, have forced important aspects of life to go underground, offering a vision of a postapocalyptic future.
—Berry Wang Mauricio Lima David Marchese W.j. Hennigan, New York Times, 2 Feb. 2026
See All Example Sentences for underground
Recent Examples of Synonyms for underground
Adjective
-
Ortiz said Rodríguez Torres went further by overseeing the creation of clandestine detention facilities.—
Antonio María Delgado,
Miami Herald,
10 Feb. 2026
-
Yes, its signage and entryway are on the clandestine side.—
Josh Miller,
Southern Living,
10 Feb. 2026
Adjective
-
The subterranean lounge is built on the garden level of a brick townhouse perched atop the hills of Mount Adams, Cincinnati's most beautiful neighborhood.—
USA TODAY NETWORK,
USA Today,
13 Feb. 2026
-
Built into an old limestone quarry, the winery felt like a Bond villain’s secret lair—sleek, subterranean, and wildly impressive.—
Condé Nast,
Condé Nast Traveler,
11 Feb. 2026
Noun
-
Against this backdrop, A-list film festivals have become vital platforms for Iranian cinema as a form of cultural resistance.—
Tina Ahmadi Krol,
HollywoodReporter,
13 Feb. 2026
-
For example, researchers envision a skin cream that protects troops from frostbite, developed by mimicking the biological cold-resistance strategies these organisms evolved over millennia.—
Ryan Brennan,
Kansas City Star,
13 Feb. 2026
Adjective
-
The No Secret Police Act banned local law enforcement officers, officers from other states and federal law enforcement personnel from wearing masks except in specific circumstances — such as in tactical, SWAT or undercover operations.—
Kevin Rector,
Los Angeles Times,
10 Feb. 2026
-
The law, Senate Bill 627, had prohibited local and federal ICE officers from wearing masks except for undercover work or health reasons.—
Kaelan Deese,
The Washington Examiner,
10 Feb. 2026
Adverb
-
Under the noses of her family, Kelly’s business team, and the revolving door of yes-people in his recording studio and homes, the book details how Kelly stealthily groomed the middle-schooler in plain sight.—
Cheyenne Roundtree,
Rolling Stone,
31 Jan. 2026
-
The unidentified white van slowly and stealthily pulled up outside the million-dollar-plus homes under the cover of darkness, grainy surveillance footage showed.—
Tribune News Service,
San Diego Union-Tribune,
31 Jan. 2026
Adjective
-
This covert expansion of sports betting is controversial.—
Jacob Stern,
The Atlantic,
5 Feb. 2026
-
The company says they can also be used for covert operations, intelligence, reconnaissance, and surveillance operations.—
Brian Sherrod,
CBS News,
4 Feb. 2026
Adverb
-
Callella, 42, is accused of using a voice over internet protocol text and call application to surreptitiously reach out to the family, but authorities were able to link the phone number to his email address and, later, his residence, according to the complaint.—
Richard Winton,
Los Angeles Times,
6 Feb. 2026
-
Fox said the exchange between him and Wasser when he was called back to the restaurant took about 10-12 seconds, but defense attorney Karen Friedman Agnifilo suggested on Monday that the pair may have surreptitiously searched the backpack at that time and found the gun — or potentially planted it.—
Ben Brachfeld,
PEOPLE,
9 Dec. 2025
Adjective
-
Get Ready: Katy Perry Has Released a Sneak Peek of Her New Song And the internet has receipts.—
Mehera Bonner,
Marie Claire,
15 Mar. 2017
Cite this Entry
“Underground.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/underground. Accessed 14 Feb. 2026.
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