under cover
1 of 3phrase
1
: in an envelope or wrapper
2
: under concealment : in secret
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 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
Julia Bonavita, FOXNews.com, 18 May 2026
Essayli on Monday confirmed that Armstrong became known to the DOJ after an undercover video was posted online by James O'Keefe, the founder of conservative nonprofit Project Veritas.
—Austin Turner, CBS News, 18 May 2026
Tax Notes Staff, Forbes.com, 28 Apr. 2026
Meanwhile, Chee goes further undercover.
—Jordan Hoffman, Entertainment Weekly, 16 Mar. 2026
See All Example Sentences for under cover
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Adjective
Gaff reportedly obliged, providing the undercover detectives with a sample that was subsequently sent through the federal database CODIS, where investigators ultimately linked him to Weaver's murder.
—Julia Bonavita, FOXNews.com, 18 May 2026
Essayli on Monday confirmed that Armstrong became known to the DOJ after an undercover video was posted online by James O'Keefe, the founder of conservative nonprofit Project Veritas.
—Austin Turner, CBS News, 18 May 2026
Noun
Nathan Richman: What was the best cover one of your undercovers had?
—Tax Notes Staff, Forbes.com, 28 Apr. 2026
Meanwhile, Chee goes further undercover.
—Jordan Hoffman, Entertainment Weekly, 16 Mar. 2026
See All Example Sentences for under cover
Cite this Entry
“Under cover.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/under%20cover. Accessed 20 May. 2026.
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