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
Synonyms
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
Eric Lagatta, USA TODAY, 6 Feb. 2025
Unaware that Kelso was an undercover brother, Torres is at the bar trying to talk Lenny into getting him in touch with Wilk.
—Sara Netzley, EW.com, 4 Feb. 2025
Shea Simmons, People.com, 6 Feb. 2025
The Confidential Rental and Leasing Office, created under former Commissioner Ray Kelly, has an important core purpose: to give investigators, including undercovers, a way to procure and use a range of vehicles that don’t automatically give them away, which standard unmarked cop cars tend to do.
—New York Daily News Editorial Board, New York Daily News, 16 Jan. 2025
See all Example Sentences for undercover 
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Adjective
This time, Reacher must help rescue an undercover DEA informant while confronting his own haunted past, according to Prime Video.
—Eric Lagatta, USA TODAY, 6 Feb. 2025
Unaware that Kelso was an undercover brother, Torres is at the bar trying to talk Lenny into getting him in touch with Wilk.
—Sara Netzley, EW.com, 4 Feb. 2025
Noun
Want to see what else is up for grabs during Wayfair’s undercover Kelly Clarkson Home sale?
—Shea Simmons, People.com, 6 Feb. 2025
The Confidential Rental and Leasing Office, created under former Commissioner Ray Kelly, has an important core purpose: to give investigators, including undercovers, a way to procure and use a range of vehicles that don’t automatically give them away, which standard unmarked cop cars tend to do.
—New York Daily News Editorial Board, New York Daily News, 16 Jan. 2025
See all Example Sentences for undercover
Dictionary Entries Near undercover
Cite this Entry
“Undercover.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undercover. Accessed 10 Feb. 2025.
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