under cover

1 of 3

phrase

Synonyms of under covernext
1
: in an envelope or wrapper
2
: under concealment : in secret

undercover

2 of 3

adjective

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

undercover

3 of 3

noun

: a person engaged in undercover activity : spy

Synonyms of under cover

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Adjective

Noun

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Examples of under cover 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
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.
Phrase
Nolan divides the sacking of Troy into two lengthy sequences, both shot under cover of darkness but edited (by Jennifer Lame) with a magisterial clarity. — Justin Chang, New Yorker, 17 July 2026 Conversely, if only the ground robots had been employed, the defenders could have remained under cover until the robots exhausted their ammunition or blocked their advance with physical obstacles. — Vikram Mittal, Forbes.com, 17 July 2026
Adjective
Pagnoni was actually communicating with an undercover detective from the Camden County Prosecutor's Office High Tech Crimes Unit. — Cbs News Philadelphia Staff, CBS News, 30 July 2026 The Watauga County Sheriff’s Office was investigating the drug target, and an undercover officer was associated with the license plate Elliott found. — Julia Coin updated July 30, Charlotte Observer, 30 July 2026
Noun
The result is that the majority — roughly 70% of public firms — of Self-Dealers and Value-Extractors still practicing MSV undercover are enjoying below-average as shown by the data in Figure 2 from Professor Felix Oberholzer’s book Better Simpler Strategy. — Steve Denning, Forbes.com, 21 June 2026 First, in February 2008, a Dutch TV station aired a confession allegedly made by van der Sloot and captured on a hidden camera by Patrick van der Eem, a businessman working undercover for a Dutch journalist. — Lynsey Eidell, PEOPLE, 30 May 2026 See All Example Sentences for under cover

Word History

First Known Use

Adjective

1920, in the meaning defined above

Noun

1962, in the meaning defined above

Time Traveler
The first known use of under cover was in 1920

Rhymes for under cover

See All Rhymes for under cover

Browse Nearby Words

undercourse
under cover
undercover
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Cite this Entry

“Under cover.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/under%20cover. Accessed 1 Aug. 2026.

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Kids Definition

undercover

adjective
un·​der·​cov·​er
-ˌkəv-ər
: acting or performed in secret
an undercover scheme
especially : employed or engaged in spying or secret investigation
an undercover agent
undercover adverb
Last Updated: - Updated example sentences
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