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
Emerson Clarridge, Fort Worth Star-Telegram, 6 May 2026
Duties include developing operation plans and going undercover.
—Angela Rodriguez
may 3, Sacbee.com, 3 May 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
Before his time at the district attorney’s office, Ferry worked undercover as a special agent for the Drug Enforcement Administration.
—Emerson Clarridge, Fort Worth Star-Telegram, 6 May 2026
Duties include developing operation plans and going undercover.
—Angela Rodriguez
may 3, Sacbee.com, 3 May 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
-
Dark, dim, and a little grungy, with its scuffed checkerboard floors, worn old couches, peeling walls, and chalkboard menus, La Factoria feels like a clandestine underground speakeasy.—
Condé Nast,
Condé Nast Traveler,
7 May 2026
-
Filling out the role of Ilya is Jay Armstrong Johnson; Jimin Moon plays Shane; Ryann Redmond plays a wine-mom narrator who lives for their clandestine love.—
Dan Stahl,
New Yorker,
1 May 2026
Adjective
-
Lothar Speer During his sentencing in 2024, federal prosecutors said the full damage caused by Rocha's decades-long covert relationship with Cuba may never be fully known.—
Sergio Candido,
CBS News,
8 May 2026
-
Ukraine has also conducted long-range covert drone strikes launched from within Russian territory, including attacks on strategic airbases using drones concealed in trucks or civilian infrastructure, demonstrating the increasing reach of low-cost UAV systems into deep strategic targets.—
Encyclopedia Britannica,
Encyclopedia Britannica,
8 May 2026
Noun
-
Hong Kong — China’s top spy agency has come out of the shadows to warn that its young people are being duped by foreign forces into shirking hard work and prioritizing their individual emotions at the expense of national development.—
Sylvie Zhuang,
CNN Money,
7 May 2026
-
Lu’s lawyer, John Carman portrayed the case as a mundane bureaucratic blip, not an international spy thriller.—
Michael R. Sisak,
Fortune,
6 May 2026
Adverb
-
Next summer, after having pupated underground, the adults emerge.—
Pamm Cooper,
Hartford Courant,
9 May 2026
-
The first step involves getting 10 million pounds of steel beams underground through a 20-foot-wide shaft—and that only covers the first container.—
Joseph Howlett,
Scientific American,
8 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
-
With a nod to its namesake, French printer Firmin Didot, the interiors are immaculate with contemporary wooden-block four-posters and a secret bookcase bathroom door in one room.—
Condé Nast,
Condé Nast Traveler,
14 May 2026
-
And Agnes is betrothed to the formidable Commander Weston, who runs the Eyes and has a secret history of domestic violence.—
Amanda Whiting,
Vulture,
13 May 2026
Noun
-
Once a loyal Republican and McCain campaign operative, her transformation to anti-Trump voice was spurred by personal experiences that have shaped her point of view.—
Los Angeles Times,
Los Angeles Times,
10 May 2026
-
An Associated Press investigation into Rocha found several red flags overlooked along the way, including a warning that one longtime CIA operative received nearly two decades ago that Rocha was working as a double agent.—
JOSHUA GOODMAN,
Arkansas Online,
10 May 2026
Adverb
-
Haslach also admitted to surreptitiously taking a photo of a minor in a swimsuit by positioning his cellphone under a classroom desk.—
Nick Ferraro,
Twin Cities,
1 May 2026
-
Sometimes the batteries on the trackers would run low, and McGovern’s team would need to remove and recharge the devices, before surreptitiously replacing them.—
Ed Caesar,
New Yorker,
30 Apr. 2026
Cite this Entry
“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 15 May. 2026.
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