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
CBS News, 28 Mar. 2026
According to charging papers, Heifler met with an undercover FBI agent on multiple occasions earlier this month and last month to discuss a plot to firebomb the woman's home.
—Natalie Neysa Alund, USA Today, 27 Mar. 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 complaint says Heifler spent weeks discussing the plot with the undercover law enforcement official, and at one point went to scope out Kiswani's home.
—CBS News, 28 Mar. 2026
According to charging papers, Heifler met with an undercover FBI agent on multiple occasions earlier this month and last month to discuss a plot to firebomb the woman's home.
—Natalie Neysa Alund, USA Today, 27 Mar. 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
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The Pozo de Vargas is considered the largest clandestine mass grave of Argentina’s last dictatorship with the remains of 149 people recovered from the site.—
Débora Rey,
Los Angeles Times,
24 Mar. 2026
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The Pozo de Vargas is considered the largest clandestine mass grave of Argentina’s last dictatorship with the remains of 149 people recovered from the site.—
ABC News,
ABC News,
22 Mar. 2026
Adjective
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Her covert affair with Davis became big news when a Chicago gossip columnist wrote a detailed account of their relationship in early 1958, including their plans to wed, despite their denials.—
Glenn Garner,
Deadline,
28 Mar. 2026
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While Iran is not known to have any interests in Uganda, it has been accused of covert operations in neighboring Kenya and Tanzania, including the running of smuggling networks and making controversial diplomatic and economic outreach with questionable motives throughout the region.—
Paul Tilsley,
FOXNews.com,
28 Mar. 2026
Noun
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But the cameras in question are not exotic spy technology.—
Deni Ellis Béchard,
Scientific American,
26 Mar. 2026
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Ezekiel Richardson outs himself as a spy for the Continental Army to Claire.—
Maggie Fremont,
Vulture,
26 Mar. 2026
Adverb
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The company plans to buy electricity from a natural gas plant to be built at the Archer Daniels Midland corn processing plant in Decatur, Illinois, where carbon dioxide emissions would be captured and stored underground.—
Tammy Webber,
Fortune,
29 Mar. 2026
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Blinken said the Democratic administrations considered military action but didn’t pursue it because Iran could retaliate and bury its nuclear program deeper underground.—
Bart Jansen,
USA Today,
28 Mar. 2026
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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The court’s comments came from a case brought by the Miami Herald that challenged keeping a portion of a grand jury’s report secret.—
Alexandra Glorioso,
Miami Herald,
26 Mar. 2026
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To acknowledge reality is to cease to be Liza Minnelli, and the secret self revealed in these pages has disappointingly few insights to share.—
Matt Weinstock,
New Yorker,
25 Mar. 2026
Noun
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The man who crashed an explosive-laden truck into a Michigan synagogue where scores of children were at daycare acted as an operative of Hezbollah, the foreign terrorist organization based in Lebanon, federal officials said March 30.—
Michael Loria,
USA Today,
31 Mar. 2026
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An operative would normally plan to walk alone to a hotel room to avoid being seen with an asset.—
David D. Kirkpatrick,
New Yorker,
30 Mar. 2026
Adverb
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Maritime tracking firm Winward suggested the ship may have spoofed its location and surreptitiously delivered the fuel to Cuba already.—
Nora Gámez Torres,
Miami Herald,
20 Mar. 2026
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Slipping surreptitiously from documentary to drama, the story of Junyi, a Catalan of Chinese decent, and his embrace of his roots, moved by the singular draw of family history, and with that a multi-cultural identity.—
Ed Meza,
Variety,
10 Mar. 2026
Cite this Entry
“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 1 Apr. 2026.
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