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
Barnini Chakraborty, The Washington Examiner, 3 Sep. 2025
The undercover detectives made their ages known.
—Darrell Smith, Sacbee.com, 3 Sep. 2025
Byron Tau, Chicago Tribune, 30 Aug. 2025
Law enforcement officers working in plain clothes or undercover is nothing new.
—Dana Taylor, USA Today, 22 Aug. 2025
See All Example Sentences for undercover
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Adjective
Senate Bill 627, for example, would prohibit law enforcement agents from covering their faces to obscure their identity, carving out exceptions for SWAT teams and undercover officers.
—Barnini Chakraborty, The Washington Examiner, 3 Sep. 2025
The undercover detectives made their ages known.
—Darrell Smith, Sacbee.com, 3 Sep. 2025
Noun
Masks were once largely forbidden on the federal level unless an agent was working undercover, said Michael Bouchard, a former assistant director at the Bureau of Alcohol, Tobacco Firearms and Explosives who retired in 2007.
—Byron Tau, Chicago Tribune, 30 Aug. 2025
Law enforcement officers working in plain clothes or undercover is nothing new.
—Dana Taylor, USA Today, 22 Aug. 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 10 Sep. 2025.
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