un·der·cov·er
ˌən-dər-ˈkə-vər 
: acting or executed in secret
specifically
: employed or engaged in spying or secret investigation
an undercover agent
undercover
adverb
Examples of undercover in a Sentence
Adjective
an undercover operation to infiltrate the terrorist organization
for months she's been an undercover agent pretending to be a drug dealer
Noun
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
Recent Examples on the Web
Christina Coulter, PEOPLE, 30 Oct. 2025
Pic follows the young protégé of a legendary crime boss, secretly an undercover cop, who is executed before revealing a file that exposes the city’s entire web of corruption.
—Jesse Whittock, Deadline, 29 Oct. 2025
Martin Suarez, Rolling Stone, 13 Sep. 2025
Season 2 of the hit Paramount+ series will continue following Martian (Michael Fassbender), a CIA agent living undercover in his own life.
—Max Goldbart, Deadline, 4 Sep. 2025
See All Example Sentences for undercover
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Adjective
Patrons helped lure her outside so undercover officers could move in, per the outlet.
—Christina Coulter, PEOPLE, 30 Oct. 2025
Pic follows the young protégé of a legendary crime boss, secretly an undercover cop, who is executed before revealing a file that exposes the city’s entire web of corruption.
—Jesse Whittock, Deadline, 29 Oct. 2025
Noun
Four other agents accompanied me, all also operating undercover.
—Martin Suarez, Rolling Stone, 13 Sep. 2025
Season 2 of the hit Paramount+ series will continue following Martian (Michael Fassbender), a CIA agent living undercover in his own life.
—Max Goldbart, Deadline, 4 Sep. 2025
See All Example Sentences for undercover
Cite this Entry
“Undercover.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undercover. Accessed 31 Oct. 2025.
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