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 investigation began earlier this week after a citizen contacted the department after an encounter with someone who claimed to be an undercover deputy sheriff. Greg Moran, sandiegouniontribune.com, "Vista man impersonates sheriff's deputy, gets arrested by actual deputies," 14 June 2018 Since 2015, Sir John Mitting launched an inquiry into undercover policing from forces across England and Wales. Amanda Arnold, The Cut, "Everything to Know About the Lush Police Campaign Controversy," 6 June 2018 Well enough to trade in her undercover work in the vice squad for scuba gear and a 50-pound vest. CBS News, "Profiles in Service: Meet the NYPD's only female counter-sniper," 2 July 2018 Speaking of undercover, 25-year-old Brett Robinson and 21-year-old Haleigh Broucher both pick season 16 winner and former police officer Derrick Levasseur as their favorite gamer. Brian Porreca, The Hollywood Reporter, "'Big Brother' Reveals New Houseguests for Season 20," 18 June 2018 The heist itself is cool, involving a lot of fancy tricks and undercover work. Josephine Livingstone, The New Republic, "In Ocean’s 8, Diamonds Are a Girl’s Best Friend," 12 June 2018 In the middle of the drug war the CIA sends Matt Graver (Brolin) to team up with former undercover operative Alejandro Gilick (del Toro) to kidnap the daughter of a drug lord, a false flag operation designed to incite rival cartels. Ariston Anderson, The Hollywood Reporter, "Ischia Global Festival to Open With 'Sicario: Day of the Soldado'," 26 June 2018 The brother and sister who run the West Gulf Bank business were both hit with drug charges after undercover police repeatedly bought marijuana extracts at the shop. Samantha Ketterer, Houston Chronicle, "North Houston smoke shop temporarily closed after police find synthetic cannabinoids," 22 June 2018 The mayor then directed the chief of police to halt the undercover stings. Ellen Mcgirt, Fortune, "raceAhead: The CEO Action for Diversity and Inclusion Turns Two and Five Breaking News Haikus," 8 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

1 Sep 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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