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Synonyms

undercover

American  
[uhn-der-kuhv-er, uhn-der-kuhv-] / ˌʌn dərˈkʌv ər, ˈʌn dərˌkʌv- /

adjective

  1. working or done out of public sight; secret.

    an undercover investigation.

    Synonyms:
    hidden, clandestine, covert
  2. engaged in spying or securing confidential information.

    an undercover agent.


undercover British  
/ ˌʌndəˈkʌvə /

adjective

  1. done or acting in secret

    undercover operations

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of undercover

First recorded in 1850–55; under- + cover

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.

“It was an opportunity to show him as someone else. He’s undercover,” says Bellizzi.

From Los Angeles Times

Jess Phillips, Minister for Safeguarding and Violence against Women and Girls, said the government is funding "a network of undercover officers online and a dedicated police taskforce to disrupt crimes, catch offenders and protect children".

From BBC

The first three seasons of "Tehran", which focused on a Mossad agent working undercover in the Iranian capital, were filmed in Athens.

From Barron's

The undercover officers donned masks depicting Captain America, Batman and Jason Voorhees from Friday the 13th, among others, to nab a pair in the act, Brazil's Civil Police said.

From BBC

But unbeknownst to him, Finlay could have been caught up in an earlier attack if the plot had not been foiled by an undercover police operative.

From BBC