1
as in clandestine
undertaken or done so as to escape being observed or known by others
an undercover operation to infiltrate the terrorist organization
Synonyms & Similar Words
Relevance
Antonyms & Near Antonyms
as in spy
a person who tries secretly to obtain information for one country in the territory of another usually unfriendly country
within the city was a well-organized fifth column, and these undercovers would make themselves known as soon as the invading forces breached the city limits
Synonyms & Similar Words
as in underground
Synonyms & Similar Words
Antonyms & Near Antonyms
Example Sentences
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Recent Examples of undercover
Liam Quinn, People.com, 11 Apr. 2025
An undercover police officer posing as a hitman conversed with Hellenthal, who allegedly explained how to access his former wife’s home and offered cash and jewelry as payment for killing her, the release stated.
—Aurora Beacon-News, Chicago Tribune, 11 Apr. 2025
Jessica Radloff, Glamour, 8 Sep. 2023
The documentary is a first time collaboration between ABC News Studios and the Associated Press following a former Army sniper undercover inside the KKK.
—ABC News, 30 Apr. 2023
See All Example Sentences for undercover
Adjective
The reported indictment alleges that one of the people was an undercover agent.
—Liam Quinn, People.com, 11 Apr. 2025
An undercover police officer posing as a hitman conversed with Hellenthal, who allegedly explained how to access his former wife’s home and offered cash and jewelry as payment for killing her, the release stated.
—Aurora Beacon-News, Chicago Tribune, 11 Apr. 2025
Noun
Back at the hospital Jack tells Brady that working undercover took a lot of courage.
—Jessica Radloff, Glamour, 8 Sep. 2023
The documentary is a first time collaboration between ABC News Studios and the Associated Press following a former Army sniper undercover inside the KKK.
—ABC News, 30 Apr. 2023
See All Example Sentences for undercover
Recent Examples of Synonyms for undercover
Adjective
-
After authorities responded with mass arrests, weavers formed clandestine committees and took secret oaths.—
John Cassidy,
New Yorker,
14 Apr. 2025
-
Til Schweiger plays a sardonic whale-tourism boat captain (and former elite military operative, obviously) who gets roped into taking down a clandestine organization that’s building the perfect super-soldier through genetic experiments.—
Jordan Crucchiola,
Vulture,
4 Apr. 2025
Adjective
-
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
Noun
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What to know about the complex, long-simmering civil war Dearlove served as Britain's top spy between 1999 and 2004, when Tony Blair was prime minister.—
Kim Hjelmgaard,
USA Today,
14 Apr. 2025
-
The astrophysicist, who keeps close tabs on orbital traffic, said that on the day of the interview (April 4), at least three objects had returned from space — two of SpaceX's Starlink broadband satellites and a 43-year-old Russian spy satellite called Kosmos 1340.—
Tereza Pultarova,
Space.com,
14 Apr. 2025
Adverb
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The flowerpot blind snake lives primarily underground, feeding exclusively on termites and ants, researchers said.—
Lauren Liebhaber,
Miami Herald,
14 Apr. 2025
-
Such restrictions only push AI use underground, increasing risk rather than reducing it.—
Cal Al-Dhubaib,
Forbes.com,
11 Apr. 2025
Adjective
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Chia seed water can also be a secret weapon for preventing traveler's constipation and supporting regular bowel movements.1 Chia Seed Nutrition Chia seeds are a small yet nutrient-dense food.—
Sohaib Imtiaz,
Verywell Health,
16 Apr. 2025
-
The secret ingredient in this chili is definitely the butter.—
Sarah Martens,
Better Homes & Gardens,
16 Apr. 2025
Noun
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Rather, Nick Badolato, a Brooklyn Conservative Party operative, collected signatures to run on the party’s line against Zhuang.—
Chris Sommerfeldt,
New York Daily News,
14 Apr. 2025
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In one case, operatives posing as art dealers interested in purchasing a work by a dissident artist secretly installed surveillance equipment in his workplace and a GPS tracker on his car.—
David Faris,
MSNBC Newsweek,
11 Apr. 2025
Adjective
-
In 2022, a consortium of private retirement-plan providers announced a collaboration to boost the portability of small retirement accounts.—
Daniel de Visé,
USA Today,
20 Apr. 2025
-
Limonite Av Eval Fire has been burning on private land.—
CA WILDFIRE BOT,
Sacbee.com,
19 Apr. 2025
Noun
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In February, OpenAI launched AI agent tool Deep Research weeks before publishing its system card.—
Hayden Field,
CNBC,
16 Apr. 2025
-
Those qualities should top your list of agent must-haves, along with clear communication and high client ratings.—
Berit Thorkelson,
Better Homes & Gardens,
16 Apr. 2025
Cite this Entry
“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 28 Apr. 2025.
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