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
Tim Dunn, Boston Herald, 28 May 2026
When Conradt didn’t show at the undercover house, NBC and police went to his home in an attempt to serve a search warrant.
—Emily St. Martin, Los Angeles Times, 27 May 2026
Martin Suarez, Rolling Stone, 13 Sep. 2025
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
See All Example Sentences for undercover
Adjective
The governor deflected to a rant about a DOJ lawsuit filed Wednesday over her refusal to reverse a RMV policy banning ICE from obtaining undercover license plates.
—Tim Dunn, Boston Herald, 28 May 2026
When Conradt didn’t show at the undercover house, NBC and police went to his home in an attempt to serve a search warrant.
—Emily St. Martin, Los Angeles Times, 27 May 2026
Noun
Four other agents accompanied me, all also operating undercover.
—Martin Suarez, Rolling Stone, 13 Sep. 2025
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
See All Example Sentences for undercover
Recent Examples of Synonyms for undercover
Adjective
-
That similarly clandestine spot is tucked in the mail sorting room of Hotel Phillips downtown.—
Kansas City Star,
Kansas City Star,
29 May 2026
-
Nicknamed Zvezdny Gorodok, or Star City/Starry Town, this clandestine base of operations was built beside the Tsiolkovskaya railway station served by the Yaroslavl Railroad.—
Jeff Spry,
Space.com,
27 May 2026
Adjective
-
In mid-January, as Iran crushed wide-scale protests with the mass killing of demonstrators, Israel prepared a covert mission along the Azerbaijan-Iran border, two of the sources familiar with the plans told CNN.—
Tal Shalev,
CNN Money,
5 June 2026
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The facility's revelation came less than two years after North Korea unveiled another covert uranium-enrichment plant in September 2024, in its first public disclosure of such a facility since showing one at the country's main Yongbyon nuclear complex to visiting American scholars in 2010.—
CBS News,
CBS News,
4 June 2026
Noun
-
Epstein had done some of his own detective work by purchasing a spy camera to catch the culprit, who turned out to be a former butler.—
Julie K. Brown,
Miami Herald,
4 June 2026
-
The Five Eyes intelligence alliance warned that China was using LinkedIn and other social media platforms to recruit spies.—
Jeronimo Gonzalez,
semafor.com,
4 June 2026
Adverb
-
Entergy New Orleans, the city’s main electric utility, has an accelerated grid-hardening plan that aims to replace existing utility poles with more fortified poles to withstand higher winds and selectively move some lines underground in high-risk areas.—
Sufan Jiang,
Fortune,
30 May 2026
-
The five went underground more than a week ago searching for gold before being trapped by rising rainwater.—
Kocha Olarn,
CNN Money,
30 May 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
-
The menu is full of twists-on-classics such as the Clean Dirty Martini, served with a frozen cube of olive juice, and the Ritz Pimms with, of course, many secret ingredients in addition to ginger ale, Champagne, and garnishes of fruit, cucumber, fresh mint and griottine cherries.—
Condé Nast,
Condé Nast Traveler,
4 June 2026
-
The story follows a furniture store owner (Chiwetel Ejiofor) who finds a secret doorway that leads him to a seemingly endless stretch of nondescript rooms.—
Rebecca Rubin,
Variety,
3 June 2026
Noun
-
Known for projects like Army of the Dead and a number for DC, including Zack Snyder’s Justice League, Snyder is currently in post on The Last Photograph, a drama following an ex-DEA operative and war photographer in search of a pair of missing children in South America.—
Matt Grobar,
Deadline,
1 June 2026
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To complete the task, Rachel needs to bring in a pair of expert extractors, Sid (Cavill) and Bronco (Gyllenhaal), and their team of covert operatives because Manny lives on an island guarded by a private army whose members are locked and loaded with high-tech weaponry.—
Tim Lammers,
Forbes.com,
1 June 2026
Adverb
-
Gray-hat hackers, unlike white-hats, surreptitiously sneak into corporate systems to find security vulnerabilities.—
Winston Cho,
HollywoodReporter,
4 June 2026
-
Scammers can create an AI replica of someone’s voice using a short recording of their speech — often pulled from social media or an earlier scam call that was surreptitiously recorded.—
CNN.com Wire Service,
Mercury News,
29 May 2026
Cite this Entry
“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 7 Jun. 2026.
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