An informant is someone who secretly provides information to police, the FBI, or another law enforcement agency. If you watch a lot of crime shows on TV, you're probably familiar with informants.

In the world of law enforcement, informants are officially called CIs, for "confidential informant" or "criminal informant." The information informants provide can be useful in catching criminals, and the informant usually gets something in return — money or a reduced prison sentence, for example. Sometimes informant simply means "person who gives information."

Definitions of informant
  1. noun
    a person who supplies information
    synonyms: source
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    betrayer, blabber, informer, rat, squealer
    one who reveals confidential information in return for money
    a surreptitious informant
    passive source
    an informant who is not assigned to obtain specific intelligence but who routinely passes on whatever information he or she has
    whistle blower, whistle-blower, whistleblower
    an informant who exposes wrongdoing within an organization in the hope of stopping it
    canary, fink, sneak, sneaker, snitch, snitcher, stool pigeon, stoolie, stoolpigeon
    someone acting as an informer or decoy for the police
    copper's nark, nark
    an informer or spy working for the police
    grass, supergrass
    a police informer who implicates many people
    type of:
    a person who communicates with others
  2. noun
    someone who sees an event and reports what happened
    synonyms: witness, witnesser
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    attestant, attester
    someone who affirms or vouches for the correctness or truth or genuineness of something
    deponent, deposer, testifier
    a person who testifies or gives a deposition
    type of:
    beholder, observer, perceiver, percipient
    a person who becomes aware (of things or events) through the senses
    speaker, talker, utterer, verbaliser, verbalizer
    someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous)
Word Family

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