whistle-blower

Noun whistle-blower has 1 sense

• whistle-blower(n = noun.person) whistle blower, whistleblower - an informant who exposes wrongdoing within an organization in the hope of stopping it; "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 in mental hospitals"
is a kind of informant, source