undercover
Americanadjective
-
working or done out of public sight; secret.
an undercover investigation.
- Synonyms:
- hidden, clandestine, covert
-
engaged in spying or securing confidential information.
an undercover agent.
adjective
Etymology
Origin of undercover
Explanation
Undercover means secret or disguised. A police department might send undercover officers dressed as clowns to investigate a corrupt circus. When this adjective was originally used in the mid-19th century, it meant "sheltered beneath something," but after a century or so, it was routinely used to mean "covert or clandestine." If you go undercover, you're doing some kind of secret work, usually inside an organization or group. If the other chess club members want you to be an undercover spy inside the French club, you'll have to brush up on your verb tenses.
Vocabulary lists containing undercover
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
“I feel like an undercover cop right now,” she says, clearly getting a rush.
From Los Angeles Times ● Oct. 16, 2026
Watching BBC undercover footage of Bechi smiling and greeting supporters at an event in March, when he should still have been in prison, Ira became tearful.
From BBC ● Oct. 8, 2026
That boosted the airline’s bottom line as multiple Tel Aviv flights leave Dubai every day from Dubai International Airport’s Terminal 3, often under the additional watch of undercover security personnel there.
From The Wall Street Journal ● Sep. 30, 2026
Gounaud was a 20-year FBI veteran who had worked on elaborate undercover operations.
From Salon ● Sep. 23, 2026
They dispatched a young-looking undercover agent, posing as a reporter for a college newspaper, to “interview” the public relations representatives at the Goodson-Todman Productions, producers of I’ve Got a Secret.
From "Endgame" by Frank Brady
Random Word
Spin the wheel and learn a new word!
Get a wordDefinitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
