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undercover

adjective un·der·cov·er \ ˌən-dər-ˈkə-vər \
Updated on: 13 May 2018

Definition of undercover

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

undercover

adverb

Examples of undercover in a Sentence

  1. an undercover operation to infiltrate the terrorist organization

  2. for months she's been an undercover agent pretending to be a drug dealer

Recent Examples of undercover from the Web

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.

First Known Use of undercover

1920

in the meaning defined above

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undercover

noun

Definition of undercover

: a person engaged in undercover activity : spy

Examples of undercover in a Sentence

  1. 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

Recent Examples of undercover from the Web

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.

First Known Use of undercover

1962

in the meaning defined above

See Words from the same year
NEW! Time Traveler

UNDERCOVER Defined for English Language Learners

undercover

Definition of undercover for English Language Learners

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



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