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
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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
Synonyms & Similar Words
Antonyms & Near Antonyms
Example Sentences
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Recent Examples of underground
Ella Gonzales, Fort Worth Star-Telegram, 4 June 2025
Archaeologists discovered the remains of thrushes in an underground waste disposal system called a cesspit connected to a taberna, or food shop, in Pollentia dating back about 2,100 years, according to a May 26 study published in the International Journal of Osteoarchaeology.
—Lauren Liebhaber, Miami Herald, 3 June 2025
Arricca Elin Sansone, Southern Living, 11 May 2025
Now throw in the fact that buying passwords on the criminal underground, be that by the way of dark web marketplaces or surface web criminal forums, is stupidly cheap.
—Davey Winder, Forbes.com, 30 Apr. 2025
Reuters, FOXNews.com, 24 May 2025
In South Africa, 289 workers are trapped underground in the Kloof gold mine's number seven shaft, according to operator Sibanye-Stillwater.
—Shane Croucher, MSNBC Newsweek, 23 May 2025
See All Example Sentences for underground
Adjective
How to find No Vacancy No Vacancy is a 3,800-square-foot underground space under Riot Room and Junk Punch.
—Ella Gonzales, Fort Worth Star-Telegram, 4 June 2025
Archaeologists discovered the remains of thrushes in an underground waste disposal system called a cesspit connected to a taberna, or food shop, in Pollentia dating back about 2,100 years, according to a May 26 study published in the International Journal of Osteoarchaeology.
—Lauren Liebhaber, Miami Herald, 3 June 2025
Noun
However, remember that this will not remove the fungi underground, just the visible mushrooms.
—Arricca Elin Sansone, Southern Living, 11 May 2025
Now throw in the fact that buying passwords on the criminal underground, be that by the way of dark web marketplaces or surface web criminal forums, is stupidly cheap.
—Davey Winder, Forbes.com, 30 Apr. 2025
Adverb
Relatives of those still in the mine, however, expressed shock and worry that their loved ones remained underground.
—Reuters, FOXNews.com, 24 May 2025
In South Africa, 289 workers are trapped underground in the Kloof gold mine's number seven shaft, according to operator Sibanye-Stillwater.
—Shane Croucher, MSNBC Newsweek, 23 May 2025
See All Example Sentences for underground
Recent Examples of Synonyms for underground
Adjective
-
Syria under Assad is believed to have operated an extensive clandestine nuclear program, which included an undeclared nuclear reactor built by North Korea in eastern Deir el-Zour province.—
Arkansas Online,
Arkansas Online,
5 June 2025
-
The only way to pre-empt detection by these IAEA watchdogs would be for Ukraine to withdraw from the nuclear Non-Proliferation Treaty and expel the atomic inspectors, but those moves would amount to trumpeting Kyiv’s clandestine quest to develop a nuclear warhead.—
Kevin Holden Platt,
Forbes.com,
1 June 2025
Adjective
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It’s headquartered in the center of the city and leads its own subterranean tours.—
Ari Daniel,
Smithsonian Magazine,
15 May 2025
-
Resist imbibing the musical equivalent of slop bowls and drink from the subterranean spring.—
Kieran Press-Reynolds,
Pitchfork,
4 June 2025
Noun
-
Orozco’s stickers of abstraction posed the question of whether abstraction—denigrated to its lowest possible level—could now serve as a last sign of resistance and redemption from the totalitarian conditions of reification.—
Benjamin H. D. Buchloh,
Artforum,
1 June 2025
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June is a month of celebration, remembrance and resistance for New York City’s LGBTQ+ community.—
Muri Assunção,
New York Daily News,
31 May 2025
Adjective
-
So is this mystery novel secretly the story of The Gilded Age and is this an undercover crossover?—
Nick Romano,
EW.com,
6 June 2025
-
The missing money controlled by Velazquez was supposed to go toward undercover narcotics operations.—
Charles Rabin,
Miami Herald,
4 June 2025
Adjective
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Striking Iran’s nuclear program would likely set off a much larger conflict in which Israel and the United States hunt for covert Iranian nuclear sites and Tehran retaliates in the Middle East and beyond.—
Richard Nephew,
Foreign Affairs,
26 May 2025
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Mon Mothma's speech Mon Mothma's covert support of the Rebels becomes public following the devastating events of the Ghorman Massacre.—
Nick Romano,
EW.com,
25 May 2025
Adjective
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Back in August 1993, an eight-year-old Harry, along with his older brother Prince William, then 11, enjoyed a private visit to Walt Disney World in Florida with Princess Diana.—
Madison E. Goldberg,
People.com,
7 June 2025
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Every room includes either a private balcony or terrace that opens up to lush gardens or Coral Sea views.—
Alli Forde,
Travel + Leisure,
6 June 2025
Cite this Entry
“Underground.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/underground. Accessed 11 Jun. 2025.
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