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
show current usage.
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Recent Examples of undercover
Beth Gazley, The Conversation, 24 Apr. 2026
Villigram was arrested on Tuesday following several days of communication with an undercover law enforcement officer, who was posing as a 15-year-old, according to an affidavit in support of the charges filed against the teacher.
—Caroline Zimmerman, Kansas City Star, 23 Apr. 2026
Byron Tau, Chicago Tribune, 30 Aug. 2025
Law enforcement officers working in plain clothes or undercover is nothing new.
—Dana Taylor, USA Today, 22 Aug. 2025
See All Example Sentences for undercover
Adjective
The conservative groups Project Veritas and the Center for Medical Progress have both used their donors’ money for undercover surveillance.
—Beth Gazley, The Conversation, 24 Apr. 2026
Villigram was arrested on Tuesday following several days of communication with an undercover law enforcement officer, who was posing as a 15-year-old, according to an affidavit in support of the charges filed against the teacher.
—Caroline Zimmerman, Kansas City Star, 23 Apr. 2026
Noun
Masks were once largely forbidden on the federal level unless an agent was working undercover, said Michael Bouchard, a former assistant director at the Bureau of Alcohol, Tobacco Firearms and Explosives who retired in 2007.
—Byron Tau, Chicago Tribune, 30 Aug. 2025
Law enforcement officers working in plain clothes or undercover is nothing new.
—Dana Taylor, USA Today, 22 Aug. 2025
See All Example Sentences for undercover
Recent Examples of Synonyms for undercover
Adjective
-
The role of the two CIA agents who were returning from destroying a clandestine drug lab in the northern Mexican state of Chihuahua remains unclear.—
Los Angeles Times,
Los Angeles Times,
25 Apr. 2026
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The role of the two CIA agents, who were returning from destroying a clandestine drug lab in the northern Mexican state of Chihuahua, remains unclear.—
CBS News,
CBS News,
25 Apr. 2026
Adjective
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Indeed, our research suggests AI chatbots could easily be used for covert advertising to manipulate their human users.—
Brian Jay Tang,
The Conversation,
24 Apr. 2026
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In a series first, Captain Sig Hansen launches an unprecedented covert scouting mission, deploying an underwater drone into the unknown waters in a bold attempt to locate the rare strain of king crab before the rest of the fleet arrives.—
Tony Maglio,
HollywoodReporter,
23 Apr. 2026
Noun
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Under the plan, FISA, which allows warrantless wiretapping of noncitizens, would be extended for three years, with new oversight guardrails and penalties for abusing the spy tool.—
Hailey Bullis,
The Washington Examiner,
23 Apr. 2026
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Around the same time, the National Reconnaissance Office decided that two of its spy satellites were surplus to requirements and offered the hardware to NASA.—
JOHN TIMMER,
ArsTechnica,
23 Apr. 2026
Adverb
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Potatoes planted in the garden a few months ago are forming potatoes underground and the plants are starting to decline.—
Tom MacCubbin,
The Orlando Sentinel,
25 Apr. 2026
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Dickson said the site readiness work is the most complicated part of the project because of the amount of major mechanics that lie underground.—
Jessica Moore,
CBS News,
24 Apr. 2026
Adjective
-
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
-
Both countries have confirmed recent talks, although details remain secret.—
Dánica Coto,
Los Angeles Times,
29 Apr. 2026
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Federal prosecutors accused Van Dyke of using top-secret information gleaned from planning the raid to make around a dozen bets on the operation on Polymarket, a prediction market where users can bet on everything from the Super Bowl to territorial gains in the war in Ukraine.—
Michael Loria,
USA Today,
28 Apr. 2026
Noun
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Authorities should also examine whether Allen was known to authorities and, if so, whether intelligence operatives could have pieced together his train travel and arrival in the president’s orbit, Shortland said.—
Justine McDaniel,
Los Angeles Times,
26 Apr. 2026
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Laron is the son of Ronnie Major, an ex-high-ranking Sin City Disciples operative, who was sentenced to over 24 years in prison in October.—
Meredith Colias-Pete,
Chicago Tribune,
25 Apr. 2026
Adverb
-
Rarely before has a name so perfectly captured the look and feel of an endeavor that has, almost surreptitiously, dug its way into a space where it’s not supposed to be.—
Carl Juste,
Miami Herald,
22 Apr. 2026
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Katas wan't recording in the front seat, so Christine, seated beside the wives in the back, surreptitiously pulled out her phone to record Bateman.—
Ryan Coleman,
Entertainment Weekly,
8 Apr. 2026
Cite this Entry
“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 1 May. 2026.
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