whistleblower vs whistle-blower

whistleblower and whistle-blower both are nouns.

Word	Noun	Adjective	Verb	Adverb
whistleblower	Yes	No	No	No
whistle-blower	Yes	No	No	No

As nouns, whistleblower and whistle-blower are synonyms defined as:

whistleblower and whistle-blower: an informant who exposes wrongdoing within an organization in the hope of stopping it

Other synonyms of whistleblower include whistle blower.

whistleblower (noun)	whistle-blower (noun)
an informant who exposes wrongdoing within an organization in the hope of stopping it	an informant who exposes wrongdoing within an organization in the hope of stopping it