undercover

[uhn-der-kuhv-er, uhn-der-kuhv-]

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

/ ˌʌndəˈkʌvə /

adjective

1. done or acting in secret

   undercover operations

Word History and Origins

Origin of undercover¹

First recorded in 1850–55; under- + cover

Example Sentences

An undercover policing inquiry heard the Metropolitan force put the family under surveillance "almost immediately" after the 18-year-old was killed in a racist attack in 1993.

Read more on BBC

Plumb was snared by an undercover police officer from the US who infiltrated an online chatroom called Abduct Lovers.

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"There was a collective failure to exercise ethical judgment about the purpose of undercover policing and the propriety of reporting on family justice campaigns," he said.

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But undercover BBC researchers caught several pharmacists trying to prescribe the medicine to beauticians to use on people who had not been clinically assessed.

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Telling Leigh he’s doing undercover classified work and can’t disclose where he lives, he starts dating her and helps to calm her fractious home life.

Read more on The Wall Street Journal

Related Words

• covert