undercover 1 of 3

adjective

ˌən-dər-ˈkə-vər How to pronounce undercover (audio)
Definition of undercovernext
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

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Antonyms & Near Antonyms
2
as in covert
working on missions in which one's objectives, activities, or true identity are not publicly revealed for months she's been an undercover agent pretending to be a drug dealer

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Antonyms & Near Antonyms

undercover

2 of 3

noun

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

undercover

3 of 3

adverb

as in underground

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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
Adjective
Emmy Rossum plays an FBI Agent who goes undercover to try to find a female serial killer who only marries lonely millionaires. — Paul Tassi, Forbes.com, 27 July 2026 Jessica Biel, Sam Richardson, Teyonah Parris and Arturo Castro also star in the film, in which Cena plays an undercover CIA agent who inadvertently gets his buddies tied up in a globe-trotting adventure. — Brendan Morrow, USA Today, 26 July 2026
Noun
Le, who was working undercover, was shot while inside his vehicle after responding to one of multiple burglaries at a cannabis business on Embarcadero near Fifth Ave. — Carlos E. Castañeda, CBS News, 11 Dec. 2025 Four other agents accompanied me, all also operating undercover. — Martin Suarez, Rolling Stone, 13 Sep. 2025 See All Example Sentences for undercover
Recent Examples of Synonyms for undercover
  1. clandestine
  2. covert
  3. spy
  4. underground
  5. private
  6. secret
  7. operative
  8. surreptitiously
Adjective
  • In the past, drug traffickers approached the community seeking to build a clandestine airstrip inside their territory.
    — ABC News, ABC News, 23 July 2026
  • The film’s trailer, guided by the unofficial Mayor of the Marquis, Billy Bob Thornton, hints at the tales of wild nights, impromptu poolside concerts, and a clandestine stairway excursion.
    — Charisma Madarang, Rolling Stone, 22 July 2026
Definition of clandestine
Adjective
  • Undersea infrastructure like optical fiber internet cables, pipelines, sensor arrays are vulnerable to covert UUV operations.
    — Aditya Jadhav, Interesting Engineering, 24 July 2026
  • Pickaxe Mountain is near Iran’s Natanz Nuclear Complex, where an explosion in July 2020, possibly caused by a covert Israeli attack, caused serious damage to the country’s nuclear program.
    — Stephanie Pappas, Scientific American, 23 July 2026
Definition of covert
Noun
  • Like Agent Kim, Han-soo and Jin-cheol are former spies and current parents.
    — Kayti Burt, Time, 27 July 2026
  • John Cena stars as a former soldier turned spy named Sean Walker who decides to reunite with his childhood Matchbox car-loving friends, played by Jessica Biel, Sam Richardson, Teyonah Parris, and Arturo Castro.
    — Jennifer Ouellette, ArsTechnica, 26 July 2026
Definition of spy
Adverb
  • Hardware undergoes extensive testing before moving underground Ensuring the reliability of every line-replaceable unit (LRU) has been a key focus throughout the Scorpius project.
    — Bojan Stojkovski, Interesting Engineering, 26 July 2026
  • Los Angeles is one of many cities across the nation fighting an epic battle to solve a multibillion-dollar problem buried underground.
    — Hannah Fry, Los Angeles Times, 25 July 2026
Definition of underground
Adjective
  • The city says state law prevents it from setting wages for private companies such as airlines, and a new provision in the state budget further restricts what local officials can do for contract workers.
    — DJ Simmons July 27, Charlotte Observer, 27 July 2026
  • And the private grading plan associated with the project, which provided engineering details for the development of private property, was completely voided, citing issues with code compliance.
    — Zuri Primos July 27, Kansas City Star, 27 July 2026
Definition of private
Adjective
  • There is no current information about Pankow returning to Outer Banks next season, and the show probably wouldn’t have blown a secret cameo in a trailer.
    — Nellie Andreeva, Deadline, 29 July 2026
  • Kelce and Swift tied the knot in a super secret ceremony at Madison Square Garden on July 3.
    — Natasha Dye, PEOPLE, 29 July 2026
Definition of secret
Noun
  • In 2018, former campaign worker Alaina Hampton filed allegations against Kevin Quinn, a loyal operative of longtime House speaker Mike Madigan — and Hampton’s supervisor.
    — The Editorial Board, Chicago Tribune, 20 July 2026
  • According to an official synopsis, season 3 of Lioness sees hidden networks, foreign operatives and personal betrayals collide, forcing Joe to walk the line between duty and home.
    — Yamillah Hurtado, PEOPLE, 16 July 2026
Definition of operative
Adverb
  • Two senior health-ministry officials, speaking anonymously, told the magazine that at least 30,000 dead (and possibly many more) was a likelier figure, and one that was corroborated by a group of first responders who collected data surreptitiously.
    — James Kirchick, The Atlantic, 29 July 2026
  • As a group of dancers surrounded her on the B-stage, she was surreptitiously harnessed into a rig that carried her aloft, limp yet belting, into the heavens, or at least into what looked like a UFO hovering over the arena.
    — Chris Willman, Variety, 7 June 2026
Definition of surreptitiously

Browse Nearby Words

undercoats
undercover
undercover agent
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Cite this Entry

“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 1 Aug. 2026.

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Nglish: Translation of undercover for Spanish Speakers

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