Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
whistle-blower is a noun meaning "an informant who exposes wrongdoing within an organization in the hope of stopping it". It carries one recorded sense.
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”
Definitions, synonyms and semantic relations for whistle-blower come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.