crazy vs lunatic

crazy and lunatic both are nouns.

Word	Noun	Adjective	Verb	Adverb
crazy	Yes	Yes	No	No
lunatic	Yes	Yes	No	No

As nouns, lunatic is a hypernym of crazy; that is, lunatic is a word with a broader meaning than crazy:

Other hypernyms of crazy include maniac.

crazy (noun)	lunatic (noun)
someone deranged and possibly dangerous	an insane person
	a reckless impetuous irresponsible person

crazy (adjective)	lunatic (adjective)
intensely enthusiastic about or preoccupied with	insane and believed to be affected by the phases of the moon
possessed by inordinate excitement
foolish; totally unsound
affected with madness or insanity
bizarre or fantastic