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undercover

[uhn-der-kuhv-er, uhn-der-kuhv-] / ˌʌn dərˈkʌv ər, ˈʌn dərˌkʌv- /
ADJECTIVE
secret, spy
Synonyms
STRONGEST
covert
WEAK
clandestine concealed confidential creep furtive hidden hole-and-corner hush-hush incognito intelligence on the Q.T. private stealth stealthy sub-rosa surreptitious under wraps underground underhand underneath
Antonyms
WEAK
known open public

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.

The director was reportedly set on posting a photo of himself and agents on social media, even though some of the British agents who were photographed work undercover.

From Salon • Apr. 24, 2026

What our undercover voters are served by the algorithm is not a complete picture of what real Welsh voters are seeing online.

From BBC • Apr. 19, 2026

During one meeting, our undercover reporter asked to be introduced to Shakil to thank him for introducing him to Tanisa and was led through to a neighbouring room where he shook Shakil's hand.

From BBC • Apr. 15, 2026

At an office off the busy Mile End Road, in east London, on a Tuesday evening in early April, our undercover reporter was receiving an instruction course in how to apply for asylum.

From BBC • Apr. 15, 2026

Wasn’t that the name of the undercover agent who had stopped him in the rest room?

From "A Confederacy of Dunces" by John Kennedy Toole

Vocabulary lists containing undercover

Secret

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