Definition of undercover in US English:

undercover

adjective

  • (of a person or their activities) involved in or involving secret work within a community or organization, especially for the purposes of police investigation or espionage.

    ‘an undercover police operation’
    • ‘How the undercover police officers managed to make their way inside was not revealed.’
    • ‘In March 1999, police began an undercover surveillance operation on the prison officer.’
    • ‘The three men were caught after an undercover surveillance operation.’
    • ‘His scam ran for three years, ending in September 2001, after a sting conducted by undercover police.’
    • ‘Two cases emphasise the need for the use of cautions in connection with police undercover operations.’
    • ‘This is the haul of alcohol seized by police in an undercover operation targeting young drinkers.’
    • ‘She pleaded guilty to offering to supply heroin to undercover police officers.’
    • ‘Metro police has 24 undercover officers who are constantly on the look out for illegal activity.’
    • ‘An undercover police officer had recorded conversations with both men.’
    • ‘Townend said he believed they were undercover police officers.’
    • ‘Two drug dealers were jailed for a total of more than seven years after an undercover police operation led to their arrests.’
    • ‘At first he suspected I was an undercover police officer and they were being set up.’
    • ‘An undercover police operation has snared eight dealers who provided a class A drugs on wheels delivery service.’
    • ‘A heroin addict caught supplying drugs to police in an undercover investigation has been jailed for four years.’
    • ‘In Ireland, the new arrivals were soon being tailed by police and undercover agents.’
    • ‘Woodall told the jury at the trial she believed Douglas was an undercover police officer from Greater Manchester.’
    • ‘During the trial, two undercover police officers gave evidence from behind a screen to protect their identities.’
    • ‘I did not go around believing that I was an undercover policeman or an Interpol agent.’
    • ‘The charges arise out of a police undercover operation in the latter part of 1998.’
    • ‘During the day, he was approached at different times by three undercover police officers and each time he sold four pills to each of them.’
    covert, secret, clandestine, private, confidential, conspiratorial, underground, surreptitious, furtive, cloak-and-dagger, hole-and-corner, hugger-mugger, back-alley, backstair, stealthy, closet
    View synonyms

adverb

  • As an undercover agent.

    ‘a special unit of the police that operates undercover’
    • ‘Actually, Yan is kicked out so he can be sent undercover to infiltrate the triad crime world.’
    • ‘Police went undercover at a Catholic mass to root out yobs who attacked the parish priest.’
    • ‘She said two police officers went undercover for three weeks in the town at the end of July, calling themselves Matt and Anne.’
    • ‘The legislation to allow us to send children undercover didn't include the selling of alcohol until December.’
    • ‘The document establishes that Plame has worked undercover within the past five years.’
    • ‘I'm going to stay undercover for the rest of my life.’
    • ‘I'm a detective working undercover with three other detectives and Noah here.’
    • ‘He contacted the TUC after the Bradford riots and spent three years working undercover.’
    • ‘The claims are made by a former British soldier who worked undercover within the IRA.’
    • ‘On my return to the UK I worked undercover against the Iranian intelligence service.’
    • ‘A stockbroker turned writer, he actually went undercover inside an authentic crime family.’
    covert, secret, clandestine, private, confidential, conspiratorial, underground, surreptitious, furtive, cloak-and-dagger, hole-and-corner, hugger-mugger, back-alley, backstair, stealthy, closet
    View synonyms

Pronunciation

undercover

/ˌəndərˈkəvər//ˌəndərˈkəvər/