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Synonyms

informer

American  
[in-fawr-mer] / ɪnˈfɔr mər /

noun

  1. a person who informs against another, especially for money or other reward.

  2. a person who informs or communicates information or news; informant.


informer British  
/ ɪnˈfɔːmə /

noun

  1. a person who informs against someone, esp a criminal

  2. a person who provides information

    he was the President's financial informer

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of informer

Middle English word dating back to 1350–1400; see origin at inform 1, -er 1

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

There is something about a healthy personality that feels repelled by a snoop, a snitch, a stool pigeon, an informer.

From Salon • Sep. 28, 2025

He had lived across the street from DeLorean’s home in San Diego County and had turned informer in hopes of leniency.

From Los Angeles Times • Jul. 24, 2024

She could not believe her husband was an informer.

From BBC • Mar. 5, 2024

A tape was later obtained by the BBC, in which Dignam admitted to being an informer for the British security services.

From BBC • Mar. 5, 2024

And certain knowledge of an informer too . . . well, that was the plum in his pudding.

From "A Clash of Kings" by George R.R. Martin