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un·​der·​cov·​er ˌən-dər-ˈkə-vər How to pronounce undercover (audio)
: acting or executed in secret
specifically : employed or engaged in spying or secret investigation
an undercover agent
undercover adverb


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: a person engaged in undercover activity : spy

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
Based on a real undercover operative, Gary Johnson was known as the best professional assassin in Houston. Declan Gallagher, EW.com, 7 June 2024 The articles involving undercover reporters were later rebuked by a British press regulator. Michael M. Grynbaum, New York Times, 4 June 2024
Blazer had been wearing a wire, working in tandem with an FBI undercover, ensnaring more than ten coaches in an elaborate plot that revealed corruption in the basketball programs at Louisville, Arizona, LSU, USC and other schools. Guy Lawson, Rolling Stone, 24 Mar. 2024 Back at the hospital Jack tells Brady that working undercover took a lot of courage. Jessica Radloff, Glamour, 8 Sep. 2023 See all Example Sentences for undercover 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'undercover.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use


1920, in the meaning defined above


1962, in the meaning defined above

Time Traveler
The first known use of undercover was in 1920

Dictionary Entries Near undercover

Cite this Entry

“Undercover.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undercover. Accessed 14 Jun. 2024.

Kids Definition


: acting or performed in secret
an undercover scheme
especially : employed or engaged in spying or secret investigation
an undercover agent
undercover adverb

More from Merriam-Webster on undercover

Last Updated: - Updated example sentences
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