whistleblower
1. [ noun ] an informant who exposes wrongdoing within an organization in the hope of stopping it
Synonyms: whistle_blower whistle-blower
Examples:

"the law gives little protection to whistleblowers who feel the public has a right to know what is going on" "the whistleblower was fired for exposing the conditions

Related terms: informant
Similar spelling:   whistle-blower
  whistle_blower
  whistlestop
  whistle_stop
  whistle_buoy