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
Related Words
Dissimilar Words
Example Sentences
Examples are automatically compiled from online sources to
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Recent Examples of undercover
Gillian Stawiszynski, Cincinnati Enquirer, 28 Sep. 2025
In Hit Man, co-written with Richard Linklater, the Glen Powell character uses a very, very small quantity of latex (and some wigs) to … go undercover with the police to thwart murder-for-hire schemes, becoming a more confident man in the process.
—Daniel Fienberg, HollywoodReporter, 26 Sep. 2025
Time, 13 Aug. 2025
Meanwhile, the police send in state trooper Billy Costigan (DiCaprio) undercover to infiltrate Costello’s crime organization.
—Erik Kain, Forbes.com, 1 Aug. 2025
See All Example Sentences for undercover
Noun
Likhith Nalla, 24, used his cellphone to communicate with the undercover officer who was posing as a 15-year-old child, according to court documents.
—Gillian Stawiszynski, Cincinnati Enquirer, 28 Sep. 2025
In Hit Man, co-written with Richard Linklater, the Glen Powell character uses a very, very small quantity of latex (and some wigs) to … go undercover with the police to thwart murder-for-hire schemes, becoming a more confident man in the process.
—Daniel Fienberg, HollywoodReporter, 26 Sep. 2025
Adverb
He is aided by Yasir Abbas, a weapons specialist; Raghuveer Singh, a sniper who served in Kashmir and Tawang; Uday Bhan, an explosives expert; and Sukhbir Singh, an Indian agent undercover in Pakistan posing as a Karachi stockbroker.
—Time, 13 Aug. 2025
Meanwhile, the police send in state trooper Billy Costigan (DiCaprio) undercover to infiltrate Costello’s crime organization.
—Erik Kain, Forbes.com, 1 Aug. 2025
See All Example Sentences for undercover
Recent Examples of Synonyms for undercover
Adjective
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There is a First World War U-boat that somehow glides from underneath Lake Michigan all the way to Croatia, commandeered by its captain, post-Armistice, for new and clandestine uses.—
Kathryn Schulz,
New Yorker,
22 Sep. 2025
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Co-created by The New York Times bestselling author Carr and season 1 creator and showrunner David DiGilio, Dark Wolf follows Ben Edwards (Taylor Kitsch) on his journey from the SEALs to the clandestine side of CIA special operations.—
Susan Young,
PEOPLE,
11 Sep. 2025
Adjective
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This model protects against allergens like pollen and pet dander, smoke, dust, and does it all from a place of covert, inoffensive design.—
Julia Harrison,
Architectural Digest,
3 Oct. 2025
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The detectives’ new case takes them to a remote Arctic research station, where a member of a covert British special forces mission has been shot dead.—
Jesse Whittock,
Deadline,
29 Sep. 2025
Noun
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Though Curry got the stats in the box score, the Buckeyes’ coverage, including a spy — usually Arvell Reese — deserves just as much credit for limiting Washington’s offense.—
Dane Brugler,
New York Times,
28 Sep. 2025
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Lisbeth Salander is part Western hero, part expert hacker, part international spy and part Pippi Longstocking.—
Anders de la Motte,
PEOPLE,
28 Sep. 2025
Adverb
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The Dachshund’s History The AKC explains that the dachshund, developed in Germany in the 17th and 18th centuries for badger hunting, was bred with short, curved legs, strong digging chests, and protective skull features to battle underground.—
Lucy Notarantonio,
MSNBC Newsweek,
30 Sep. 2025
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In the early 20th century Midwest USA, deep underground, a group of coal miners make an incredible discovery.—
Christian Blauvelt,
IndieWire,
30 Sep. 2025
Adjective
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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
Adjective
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Other potential Marvel projects on the horizon include Doctor Strange 3, a secret project produced by Scarlett Johansson, and another Deadpool-adjacent mutant movie featuring Ryan Reynolds.—
Wesley Stenzel,
Entertainment Weekly,
2 Oct. 2025
-
It was intended to be kept secret.—
Dave Smith,
Fortune,
2 Oct. 2025
Noun
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Privately, political operatives from both sides concede that government shutdowns are bad for both parties.—
Nick Lichtenberg,
Fortune,
1 Oct. 2025
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Once the candidate is defined with a platform backfilled with extensive details, then allow the political operatives to take that platform out into social media with an out-of-the-box approach like some of the earlier suggestions.—
Jordan King,
MSNBC Newsweek,
30 Sep. 2025
Adverb
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Is he humiliated by being asked to leave surreptitiously for Olivia’s amusement, or is this a game for him too?—
Keith Phipps,
Vulture,
26 Sep. 2025
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In many cases, fans were able to see that the tickets were surreptitiously forwarded to unrecognized accounts, presumably so they could be sold on third-party sites.—
Jacob Feldman,
Sportico.com,
24 Sep. 2025
Cite this Entry
“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 6 Oct. 2025.
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