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
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Recent Examples of undercover
Andrea Klick, Oc Register, 10 Feb. 2026
Pisano exited the longtime procedural as a series regular back in October, with his character leaving SVU to accept an undercover assignment for the DEA in San Diego, targeting drug runs.
—Rosy Cordero, Deadline, 10 Feb. 2026
Dana Taylor, USA Today, 22 Aug. 2025
He is aided by Yasir Abbas, a weapons specialist; Raghuveer Singh, a sniper who served in Kashmir and Tawang; Uday Bhan, an explosives expert; and Sukhbir Singh, an Indian agent undercover in Pakistan posing as a Karachi stockbroker.
—Time, 13 Aug. 2025
See All Example Sentences for undercover
Adjective
The law makes exceptions for SWAT teams, undercover operations and medically or situationally necessary face coverings.
—Andrea Klick, Oc Register, 10 Feb. 2026
Pisano exited the longtime procedural as a series regular back in October, with his character leaving SVU to accept an undercover assignment for the DEA in San Diego, targeting drug runs.
—Rosy Cordero, Deadline, 10 Feb. 2026
Noun
Law enforcement officers working in plain clothes or undercover is nothing new.
—Dana Taylor, USA Today, 22 Aug. 2025
He is aided by Yasir Abbas, a weapons specialist; Raghuveer Singh, a sniper who served in Kashmir and Tawang; Uday Bhan, an explosives expert; and Sukhbir Singh, an Indian agent undercover in Pakistan posing as a Karachi stockbroker.
—Time, 13 Aug. 2025
See All Example Sentences for undercover
Recent Examples of Synonyms for undercover
Adjective
-
Treasury also sanctioned associates, companies and vessels allegedly involved in a network used by Maduro’s former oil minister, Tareck El Aissami, to evade sanctions and resell Venezuelan crude through clandestine channels.—
Antonio María Delgado,
Miami Herald,
17 Feb. 2026
-
Earlier this month, state officials reported dismantling a clandestine drug laboratory located south of Ensenada, marking the ninth such laboratory shut down by authorities in the span of a year.—
Alexandra Mendoza,
San Diego Union-Tribune,
15 Feb. 2026
Adjective
-
The historic Vietnamese revolutionary Ho Chi Minh is said to have used the hotel as a covert meeting spot during the First Indochina War.—
Sofia Celeste,
Footwear News,
14 Feb. 2026
-
What else is going on A Southern California man was sentenced to four years in prison for acting as a covert Chinese agent while helping elect an Arcadia City Council member.—
James Rainey,
Los Angeles Times,
11 Feb. 2026
Noun
-
He was also sanctioned by the European Union in January 2019 following a nerve agent attack in Salisbury, England, which the British government said was carried out by GRU agents to poison a former Russian spy.—
Anna Chernova,
CNN Money,
6 Feb. 2026
-
That unusual role for a spy chief raised additional questions from Democrats on the House and Senate intelligence committees.—
DAVID KLEPPER THE ASSOCIATED PRESS,
Arkansas Online,
5 Feb. 2026
Adverb
-
The Legislature should establish clear safety standards, age limits, labeling, and enforcement, rather than bans that push the market underground and make consumers less safe.—
Eleanor Dearman,
Fort Worth Star-Telegram,
14 Feb. 2026
-
Most of the film was shot underground in Iran.—
Nick Vivarelli,
Variety,
14 Feb. 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
-
TikToks promising secret loopholes, Reddit threads dissecting deductions and content creators insisting ways to outsmart the IRS.—
Miriam Fauzia,
Dallas Morning News,
18 Feb. 2026
-
Dry onion soup mix is the secret shortcut to lots of flavor.—
Jenna Sims,
Southern Living,
18 Feb. 2026
Noun
-
Banuelos names Bowen as the political operative who allegedly pressured city staffers.—
Alice Yin,
Chicago Tribune,
16 Feb. 2026
-
His espionage thriller Lioness, which stars Nicole Kidman and Zoe Saldaña as CIA operatives, is in production on its third season.—
Uwa Ede-Osifo,
Dallas Morning News,
16 Feb. 2026
Adverb
-
Callella, 42, is accused of using a voice over internet protocol text and call application to surreptitiously reach out to the family, but authorities were able to link the phone number to his email address and, later, his residence, according to the complaint.—
Richard Winton,
Los Angeles Times,
6 Feb. 2026
-
Fox said the exchange between him and Wasser when he was called back to the restaurant took about 10-12 seconds, but defense attorney Karen Friedman Agnifilo suggested on Monday that the pair may have surreptitiously searched the backpack at that time and found the gun — or potentially planted it.—
Ben Brachfeld,
PEOPLE,
9 Dec. 2025
Cite this Entry
“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 20 Feb. 2026.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
