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
Julia Marnin, Miami Herald, 30 Sep. 2025
Nearly 10 years after his demise, Holliday decides to go undercover as Powers to try and get a second chance with a struggling college team at South Georgia.
—Caroline Blair, PEOPLE, 30 Sep. 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
One person Smith communicated with was an undercover FBI agent, according to prosecutors.
—Noun
Four other agents accompanied me, all also operating undercover.
—Cite this Entry
“Undercover.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undercover. Accessed 3 Oct. 2025.
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