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
Olivia B. Waxman, Time, 30 Apr. 2025
The 15-year-old expression is a rich and full-bodied tequila that was aged in American and French oak in an underground cellar about 1,180 meters above sea level.
—Jonah Flicker, Robb Report, 29 Apr. 2025
Kyle Martin, The Mercury News, 24 Jan. 2025
In the ever-evolving cyber underground, ransomware extortionists have grown to become perhaps the most sophisticated and formidable threat.
—Etay Maor, Forbes.com, 26 Mar. 2025
EW.com, 25 Apr. 2025
The key to this method is in fiber-optic cables that react to disturbances underground.
—Jack Knudson, Discover Magazine, 25 Apr. 2025
See All Example Sentences for underground
Adjective
Her husband escaped from the camp, and a priest hid him in a church, part of an underground movement of South Vietnamese people.
—Olivia B. Waxman, Time, 30 Apr. 2025
The 15-year-old expression is a rich and full-bodied tequila that was aged in American and French oak in an underground cellar about 1,180 meters above sea level.
—Jonah Flicker, Robb Report, 29 Apr. 2025
Noun
The city this month began drilling at Del Prado Park, the first of several sites being explored to find safe, potable water underground.
—Kyle Martin, The Mercury News, 24 Jan. 2025
In the ever-evolving cyber underground, ransomware extortionists have grown to become perhaps the most sophisticated and formidable threat.
—Etay Maor, Forbes.com, 26 Mar. 2025
Adverb
The city had been established in its current location because the water available underground supported the population during the dry season.
—EW.com, 25 Apr. 2025
The key to this method is in fiber-optic cables that react to disturbances underground.
—Jack Knudson, Discover Magazine, 25 Apr. 2025
See All Example Sentences for underground
Recent Examples of Synonyms for underground
Adjective
-
He was allegedly held in a clandestine detention site and tortured by intelligence agents.—
Antonio Maria Delgado,
Miami Herald,
30 Apr. 2025
-
Guests can order craft cocktails at the circular bar, and for those who indulge, there’s a small, clandestine cigar room just off the entrance.—
John Wogan,
Travel + Leisure,
23 Apr. 2025
Adjective
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This zone lasts up to three months per application and guides foraging subterranean termites to bait stations.—
Jason Phillips,
USA Today,
1 May 2025
-
Raphael Martinez Cohen and Ryan Bush’s basement studio in Maspeth, Queens, feels a bit like a grotto, with shimmering panels propped up against subterranean walls.—
Hannah Martin,
Architectural Digest,
30 Apr. 2025
Noun
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Chromium uses chemicals to preserve the animal's skin, and offers more water and heat resistance for the leather products it's applied to.—
Gia Yetikyel,
Vogue,
26 Apr. 2025
-
Moto Watch Fit Features Explained The Motorola Watch Fit also has the 5ATM water resistance required to make use while swimming a reasonable idea.—
Andrew Williams,
Forbes.com,
25 Apr. 2025
Adjective
-
The Han Solo bon mot is reminiscent of Diego Luna's confusion when he is asked about smoothing some of Cassian Andor's rougher edges to go undercover as fashion designer Varian Skye in the second block of Andor season 2 episodes.—
Maureen Lee Lenker,
EW.com,
1 May 2025
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Next up, he’s set to star alongside Bryce Dallas Howard and Sean Bean in the action comedy Deep Cover, about a group of improv actors who are asked to go undercover.—
Keith Langston,
People.com,
15 Apr. 2025
Adjective
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After the unexpected death of the pope, Cardinal Lawrence (Ralph Fiennes) is tasked with running the covert process of choosing a new leader.—
Saman Shafiq,
USA Today,
22 Apr. 2025
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Those documents gave curious readers more details about Cold War-era covert U.S. operations in other nations, but did not initially lend credence to long-circulating conspiracy theories about who killed JFK.—
Josh Funk and Haya Panjwani,
Los Angeles Times,
18 Apr. 2025
Adjective
-
And when the owner of the second-largest private company in the United States speaks, there’s an oracle-like aura that demands parsing.—
Philip Elliott,
Time,
2 May 2025
-
Save for a few interviews, Rihanna and Rocky, who have been together since 2020, have kept the details of their young sons' lives private.—
Kayla Grant,
People.com,
1 May 2025
Cite this Entry
“Underground.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/underground. Accessed 5 May. 2025.
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