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
Martin Suarez, Rolling Stone, 13 Sep. 2025
The bill would prohibit federal and local law enforcement officers from wearing masks that obscure their identity during public-facing operations, with exemptions for medical and undercover purposes.
—Amelia Wu, Sacbee.com, 12 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
Martin Suarez is the only deep-undercover FBI agent in history to have infiltrated a Colombian drug cartel.
—Martin Suarez, Rolling Stone, 13 Sep. 2025
The bill would prohibit federal and local law enforcement officers from wearing masks that obscure their identity during public-facing operations, with exemptions for medical and undercover purposes.
—Amelia Wu, Sacbee.com, 12 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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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
-
The Bundy family’s statement noted this and said their destination was not clandestine, as the FBI document alleged.—
Nicole Blanchard,
Idaho Statesman,
7 Sep. 2025
Adjective
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Moreover, the lobster boat and the Mako were covert FBI assets carefully disguised as legitimate smuggling vessels.—
Martin Suarez,
Rolling Stone,
13 Sep. 2025
-
If compromised, malicious radios inside them could be used for simultaneous outages or covert data collection, the FHWA warned.—
Sujita Sinha,
Interesting Engineering,
11 Sep. 2025
Noun
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This is mostly an over-the-top spy thriller with wild shootouts, great suspense and some really intense action, but this scene took it to another level entirely.—
Erik Kain,
Forbes.com,
15 Sep. 2025
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Padrino accused Washington of sharply intensifying aerial surveillance of Venezuela, citing a surge in spy flights last month.—
Antonio María Delgado,
Miami Herald,
15 Sep. 2025
Adverb
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The species typically live a solitary life underground, but sometimes a heavy rain completely floods caves and the fish can find crevices and small openings to go from cave to cave.—
Karl Schneider,
IndyStar,
17 Sep. 2025
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Deep underground, there is resentment between two families fueled by a claustrophobic enviroment, while the super rich guests are looked after by workers clad in orange.—
Max Goldbart,
Deadline,
16 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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However trying to keep plot points secret in a social media age with fans also filming and sharing clips of the cast filming online was a battle Han had to take extra measures for.—
Lexy Perez,
HollywoodReporter,
18 Sep. 2025
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If the name is unfamiliar to you, that’s because Gur is fashion’s best kept secret.—
Nina-Sophia Miralles,
Forbes.com,
18 Sep. 2025
Noun
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Israeli airstrikes on Doha that killed Hamas operatives have intensified regional drama and prompted emergency meetings of Arab and Islamic leaders in the Qatari capital on September 14.—
Kapil Kajal,
Interesting Engineering,
15 Sep. 2025
-
Jayson is not entirely thrilled that two of his operatives are dead and their child, Sam, is missing.—
Grace Byron,
Vulture,
15 Sep. 2025
Adverb
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If some have surreptitiously slipped into the cart, throw them under the (school) bus.—
Catharine Kaufman,
San Diego Union-Tribune,
15 Sep. 2025
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By the episode's end, however, he's set his sights on Morgan, having surreptitiously slipped a note into her grocery bag.—
Randall Colburn,
Entertainment Weekly,
6 Sep. 2025
Cite this Entry
“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 21 Sep. 2025.
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