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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The Square, from South Korean director Bo-Sol Kim, which blends political commentary with experimental animation in its story of a Swedish diplomat in Pyongyang who begins a clandestine affair with a local traffic officer, took the jury prize of the Contrechamps section.—
Scott Roxborough,
HollywoodReporter,
14 June 2025
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During the early stages of the COVID-19 pandemic, Alcala — without school authorization — took wrestling mats from El Modena, had the wrestling team load them into a U-Haul truck, and then took them to a warehouse for clandestine practices, Plaintiff Two said.—
Scott Schwebke,
Oc Register,
13 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
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Ari Levinson in The Red Sea Diving Resort (2019) Inspired by a true story, Evans stars in this 2019 Netflix spy thriller as a Mossad agent named Ari Levinson.—
Devan Coggan,
EW.com,
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
-
Many in Israel see such a confrontation as the best option—even though Iran’s nuclear facilities are spread across its territory, and some are buried deep underground, making any military campaign likely to be drawn-out, complicated, and hazardous.—
Arash Azizi,
The Atlantic,
12 June 2025
Adjective
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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
-
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
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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The government has no place in his private bedrooms.—
Jenna Sundel
Joshua Rhett Miller,
MSNBC Newsweek,
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 21 Jun. 2025.
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