un·​der·​cov·​er | \ˌən-dər-ˈkə-vər \

Definition of undercover 

(Entry 1 of 2)

: acting or executed in secret specifically : employed or engaged in spying or secret investigation an undercover agent



Definition of undercover (Entry 2 of 2)

: a person engaged in undercover activity : spy

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Other Words from undercover


undercover adverb

Examples of undercover in a Sentence


an undercover operation to infiltrate the terrorist organization for months she's been an undercover agent pretending to be a drug dealer


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
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Recent Examples on the Web: Adjective

The June 14 arrest followed another prostitution arrest on April 5, 2017, when a Lake County Sheriff’s Office task force sent an undercover agent into Gem Spa. Rick Kambic, chicagotribune.com, "Following prostitution arrest, Mundelein suspends spa's business license," 10 July 2018 Three of his followers were undercover FBI agents, according to testimony in the case. Julian Hattem, The Seattle Times, "Militia leader who tried to bomb federal cabin released," 9 July 2018 During the investigation, Cortez had been identified as a person of interest in the case and undercover agents had purchased explosives from him before he was arrested, the ATF said. Joseph A. Gambardello, Philly.com, "Delco man arrested with cache of explosives like those used in Philly ATM blasts," 5 July 2018 Jonathan Rhys Meyers plays an undercover Mossad agent on a deadly mission to Syria in Daniel Zelik Berk's period spy thriller. Stephen Dalton, The Hollywood Reporter, "'Damascus Cover': Film Review," 4 July 2018 Because the incident was part of an undercover investigation, officials are not releasing the names of the officers or the location of the motel. Megan Cassidy, SFChronicle.com, "Two Alameda County sheriff’s investigators survive potentially lethal fentanyl exposure," 26 June 2018 The North American victory suggests football officials are ready to gather for a World Cup in a country whose government has demonstrated its willingness to jail corrupt sports leaders through undercover investigations. Rob Harris And Graham Dunbar, The Christian Science Monitor, "US, Canada, Mexico win joint 2026 World Cup bid," 13 June 2018 Detectives from the Poway Criminal Apprehension Team launched an investigation into the spa and conducted an undercover investigation on Wednesday, according to the press release. Emily Sorensen, Pomerado News, "Prostitution arrest made at Poway spa," 7 June 2018 The arrests were made as part of Operation Guardians of Innocence II, an undercover investigation into child pornography, WTSP reported. Natalie Dreier, ajc, "Child porn investigation: Disney World, Legoland employees among 11 arrested," 7 June 2018

Recent Examples on the Web: Noun

Police made seven undercover buys from Degan between December and early February and arrested him on Feb. 7, the document said. Travis Andersen, BostonGlobe.com, "Winthrop man pleads not guilty to drug charges; $1 million in cash seized," 23 May 2018 Haspel has spent most of her 33-year CIA career undercover, and her role in the George W. Bush administration interrogation and detention program has generated significant opposition to her selection. Jeremy Herb, CNN, "Warner asks Haspel to fix 'unacceptable' public disclosure of her record," 7 May 2018 Haspel, who has spent the majority of her CIA career undercover, is facing public scrutiny for the first time. Emily Cadei, sacbee, "Feinstein has had Gina Haspel over for dinner, but has 'deep concerns' about the CIA nominee | The Sacramento Bee," 8 May 2018 The intelligence community has largely rallied around the nomination of Haspel, who spent most of her career in the CIA undercover. Manu Raju And Jeremy Herb, CNN, "Trump's CIA pick faces growing Hill scrutiny over destruction of interrogation tapes," 17 Apr. 2018 Linna enlists a colleague, Saga Bauer, to enter the hospital undercover. Ken Tucker, New York Times, "‘The Silence of the Lambs’ Goes Nordic Noir," 13 Apr. 2018 WrestleMania 30 at the Mercedes-Benz Superdome in New Orleans, Charlotte was an extra (undercover), helping lead Triple H to the ring. Jim Varsallone, miamiherald, "WrestleMania 34 is full of Flair, but Rousey, Nicholas steal the show | Miami Herald," 9 Apr. 2018 Russell, in character as Elizabeth Jennings, a KGB agent living undercover in the United States in the waning days of the Cold War, was dispensing some tough love to her daughter, Paige (Taylor) a college student sympathetic to the Soviet cause. Meredith Blake, latimes.com, "'The Americans' prepares to take a final bow on FX," 21 Mar. 2018 The undercovers bought 10 devices from him and six-month subscriptions for $20,000, the document says. Kristina Davis, sandiegouniontribune.com, "FBI bust aims to shut drug traffickers out of their super-encrypted communication networks," 15 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'undercover.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of undercover


1920, in the meaning defined above


1962, in the meaning defined above

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Last Updated

27 Oct 2018

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Time Traveler for undercover

The first known use of undercover was in 1920

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English Language Learners Definition of undercover

: done or working in a secret way in order to catch criminals or collect information

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