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
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Antonyms & Near Antonyms
as in resistance
a secret organization in a conquered country fighting against enemy forces
joined the underground while still a teenager
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as in undercover
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Examples Sentences
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Recent Examples of underground
Chris Pandolfo, Fox News, 28 Dec. 2024
An underground nuclear-waste repository in New Mexico’s southern desert also receives federal funding; after a fire and an unrelated radiological release at the facility, ten years ago, the Department of Energy spent nearly five hundred million dollars on an update to its safety infrastructure.
—Abe Streep, The New Yorker, 27 Dec. 2024
Jonah Walters, Longreads, 24 Oct. 2024
Even before the country’s founding in 1948, the Zionist underground movement assassinated British military officers and police, seeing them as obstacles to creating a Jewish state.
—Dan De Luce, NBC News, 20 Sep. 2024
Saleen Martin, USA TODAY, 5 Dec. 2024
In recent years, California’s power companies have been doing just that: insulating power lines and burying lines underground, trimming trees, deploying drones and using risk-detection technology.
—Calmatters, The Mercury News, 4 Dec. 2024
See all Example Sentences for underground 
Adjective
Israeli troops located and destroyed a more than 300-foot-long underground tunnel used by Hezbollah's Radwan Forces as a terrorist hideout, the IDF said Saturday.
—Chris Pandolfo, Fox News, 28 Dec. 2024
An underground nuclear-waste repository in New Mexico’s southern desert also receives federal funding; after a fire and an unrelated radiological release at the facility, ten years ago, the Department of Energy spent nearly five hundred million dollars on an update to its safety infrastructure.
—Abe Streep, The New Yorker, 27 Dec. 2024
Noun
During the call, my dad reminisced about his childhood on an Air Force base in New Mexico, where everyone would gather overnight in a vast underground bunker during fallout drills.
—Jonah Walters, Longreads, 24 Oct. 2024
Even before the country’s founding in 1948, the Zionist underground movement assassinated British military officers and police, seeing them as obstacles to creating a Jewish state.
—Dan De Luce, NBC News, 20 Sep. 2024
Adverb
Their nests are usually underground though, as well as near roots of large trees.
—Saleen Martin, USA TODAY, 5 Dec. 2024
In recent years, California’s power companies have been doing just that: insulating power lines and burying lines underground, trimming trees, deploying drones and using risk-detection technology.
—Calmatters, The Mercury News, 4 Dec. 2024
See all Example Sentences for underground
Recent Examples of Synonyms for underground
Adjective
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Samia shows up in London, allegedly to attend a conference, and Brandon rekindles their clandestine romance despite her suspicious security detail (A Real Pain‘s Kurt Egyiawan) sniffing about.David Fear, Rolling Stone, 30 Dec. 2024
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Be on the lookout for people engaging in clandestine connections.Lisa Stardust, People.com, 7 Dec. 2024
Adjective
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But influence machines were once subterranean: Few people would have known about the political influence machine that the Koch brothers built in the past several decades if not for the work of investigative journalists.Ali Breland, The Atlantic, 9 Dec. 2024
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While orbiting Jupiter, Clipper will fly by Europa dozens of times and use its array of scientific instruments to study the dynamics of the moon’s subterranean ocean and look for organic compounds, a potential indicator of life.Noah Haggerty, Los Angeles Times, 14 Oct. 2024
Noun
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This shift helps move from resistance to collaboration, allowing both partners to explore what adjustments or compromises would make the decision feel right.Mark Travers, Forbes, 21 Dec. 2024
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The Senate report highlights Alito's resistance to recuse himself from cases involving President-elect Donald Trump or the January 6, 2021, U.S. Capitol riot after flags associated with the insurrection were seen flying at two of his homes.Gord Magill, Newsweek, 21 Dec. 2024
Adjective
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These are the primary takeaways from Mr. and Mrs. Smith, the Amazon Prime series that took the Pitt-Jolie movie and turned it on its head by zeroing in on the smaller issues with being undercover as a married couple.Brian Grubb, Vulture, 26 Dec. 2024
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One’s an undercover spy who kills people and the other one’s an assassin on a murderous rampage for revenge.Carita Rizzo, Deadline, 15 Dec. 2024
Adjective
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With some help from Past Lives star Teo Yoo, who plays newcomer Jang Kyun, Owen begins a covert operation for the Central Intelligence Agency, despite being a lawyer.Christy Piña, The Hollywood Reporter, 2 Jan. 2025
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This covert symbol was meant to communicate that the British were rowing across the Charles River, rather than marching on land.Sarah Kuta, Smithsonian Magazine, 2 Jan. 2025
Adjective
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What is the best way to stay private, secure and anonymous while browsing the web?Kurt Knutsson, CyberGuy Report, Fox News, 1 Jan. 2025
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Utilities, food and dining out are affordable, and healthcare is either free or inexpensive under Spain’s public or private systems.Laura Begley Bloom, Forbes, 1 Jan. 2025
Thesaurus Entries Near underground
Cite this Entry
“Underground.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/underground. Accessed 9 Jan. 2025.
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