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
Synonyms & Similar Words
Antonyms & Near Antonyms
Example Sentences
Examples are automatically compiled from online sources to
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Recent Examples of undercover
Thomas Brewster, Forbes.com, 3 June 2025
Quiet Skies, which began in 2010, employs analysts and undercover air marshals to monitor people in airports and during flights, using outstanding warrants, facial recognition software, identification of suspicious travel patterns and behaviors and other data to try to prevent terrorist attacks.
—Jennifer Jacobs, CBS News, 3 June 2025
Jessica Radloff, Glamour, 8 Sep. 2023
The documentary is a first time collaboration between ABC News Studios and the Associated Press following a former Army sniper undercover inside the KKK.
—ABC News, 30 Apr. 2023
See All Example Sentences for undercover
Adjective
He was caught out by undercover agents posing as interested parties, according to the DOJ.
—Thomas Brewster, Forbes.com, 3 June 2025
Quiet Skies, which began in 2010, employs analysts and undercover air marshals to monitor people in airports and during flights, using outstanding warrants, facial recognition software, identification of suspicious travel patterns and behaviors and other data to try to prevent terrorist attacks.
—Jennifer Jacobs, CBS News, 3 June 2025
Noun
Back at the hospital Jack tells Brady that working undercover took a lot of courage.
—Jessica Radloff, Glamour, 8 Sep. 2023
The documentary is a first time collaboration between ABC News Studios and the Associated Press following a former Army sniper undercover inside the KKK.
—ABC News, 30 Apr. 2023
See All Example Sentences for undercover
Recent Examples of Synonyms for undercover
Adjective
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Syria under Assad is believed to have operated an extensive clandestine nuclear program, which included an undeclared nuclear reactor built by North Korea in eastern Deir el-Zour province.—
Arkansas Online,
Arkansas Online,
5 June 2025
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The only way to pre-empt detection by these IAEA watchdogs would be for Ukraine to withdraw from the nuclear Non-Proliferation Treaty and expel the atomic inspectors, but those moves would amount to trumpeting Kyiv’s clandestine quest to develop a nuclear warhead.—
Kevin Holden Platt,
Forbes.com,
1 June 2025
Adjective
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Russia's latest barrages followed last weekend's covert Ukrainian operation in which agents used more than 100 drones concealed in large trucks to attack strategic bomber bases deep inside Russia.—
David Brennan,
ABC News,
8 June 2025
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Russia’s attacks on Friday come two days after Russian President Vladimir Putin vowed to retaliate against Ukraine for its highly successful Operation Spider’s Web covert strike on Russia on June 1.—
Christopher Tremoglie,
The Washington Examiner,
6 June 2025
Noun
-
Israeli Minister of Strategic Affairs Ron Dermer and the head of Israel's spy agency, Mossad chief David Barnea, were also expected to meet with Witkoff.—
Francesca Chambers,
USA Today,
13 June 2025
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Kennedy met with the CIA after a 1955 tour of the Soviet Union, relaying his observations to the spy agency as a voluntary informant, the documents show.—
Arkansas Online,
Arkansas Online,
13 June 2025
Adverb
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Some facilities are buried deep underground to put them out of reach of Israel’s weapons.—
Mostafa Salem,
CNN Money,
13 June 2025
-
Daniel: For the past nine years, she’s spent a lot of time deep underground in a prehistoric cave near the border of Wyoming and Montana.—
Ari Daniel,
Smithsonian Magazine,
12 June 2025
Adjective
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This includes every identity and associated account used for integrations, service accounts or any other technology that requires authentication based on an account or secret.—
Morey Haber,
Forbes.com,
16 June 2025
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June 16, 2025 Hiding inside every apple is a little bit of secret geometry.—
Steven Strogatz,
New York Times,
16 June 2025
Noun
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Le Carré’s description of CIA-style abductions, where massed operatives overwhelm their target, bind his hands, and dress him in black goggles and headphones engineered to block all sight and sound of the outside world, derives from contemporary journalistic accounts.—
Rav Grewal-Kök
June 16,
Literary Hub,
16 June 2025
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The Republican operative Karl Rove has written an admiring book on McKinley.—
Daniel Immerwahr,
New Yorker,
16 June 2025
Adjective
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Back in August 1993, an eight-year-old Harry, along with his older brother Prince William, then 11, enjoyed a private visit to Walt Disney World in Florida with Princess Diana.—
Madison E. Goldberg,
People.com,
7 June 2025
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Along with developing a comprehensive rebuilding master plan and supporting the Palisades’ infrastructure reconstruction, AECOM will help coordinate broader public and private rebuilding efforts.—
Julia Wick,
Los Angeles Times,
6 June 2025
Noun
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This is particularly crucial in real estate, where agents can provide guidance on flood zones, mitigation and insurance. 5.—
Frank Rojas,
Forbes.com,
16 June 2025
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Matsuoka began his media career at International Creative Management in Los Angeles as an agent trainee and has since spent his career bridging Hollywood and the Japanese film and television industry.—
Scott Feinberg,
HollywoodReporter,
16 June 2025
Cite this Entry
“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 19 Jun. 2025.
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