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
Miami Herald, 3 June 2026
Comeaux also said undercover officers would focus on drug enforcement.
—Matthew Ablon, CBS News, 1 June 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
Troopers arrange undercover purchase, FHP says Investigators arranged to purchase the gauge from the seller in Bradenton, according to a news release.
—Miami Herald, 3 June 2026
Comeaux also said undercover officers would focus on drug enforcement.
—Matthew Ablon, CBS News, 1 June 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
-
Some may be announced publicly; others may happen in more clandestine ways.—
Eben Novy-Williams,
Sportico.com,
10 June 2026
-
But clandestine flows aren’t the biggest factor behind the market calm.—
Matt Egan,
CNN Money,
9 June 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
-
That blaze continued to smolder underground and, prosecutors allege, resurfaced on January 7 and exploded into the Palisades Fire.—
Jack Hannah,
CNN Money,
7 June 2026
-
The second quake was less than 8 miles underground.—
Harry Harris,
Mercury News,
7 June 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
-
That it was spliced with footage of his secret ex-girlfriend, Meija Moreno, confessing to Ciara Miller and Kyle Cooke via FaceTime that West had lied like crazy about their relationship status portended certain doom.—
Marlow Stern,
Variety,
10 June 2026
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Trump then told reporters about a secret military mission to ensure safe passage for oil tankers through the Strait of Hormuz, one of the world’s most important commercial waterways.—
Ana Ceballos,
Los Angeles Times,
10 June 2026
Noun
-
Applewhaite is among the Democratic operatives publicly criticizing the Biden's public reemergence in recent days — especially Jill Biden's book tour.—
ABC News,
ABC News,
6 June 2026
-
The anti-establishment narrative from Lahn, who resides on his longtime family farm and owns an investment company, has been targeted by Democrats for his years of work as a GOP political operative.—
Ramsey Touchberry,
The Washington Examiner,
6 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 11 Jun. 2026.
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