rapist vs criminal

rapist and criminal both are nouns.

Word	Noun	Adjective	Verb	Adverb
rapist	Yes	No	No	No
criminal	Yes	Yes	No	No

As nouns, criminal is a hypernym of rapist; that is, criminal is a word with a broader meaning than rapist:

rapist: someone who forces another to have sexual intercourse
criminal: someone who has committed a crime or has been legally convicted of a crime

Other hypernyms of rapist include aggressor, assailant, assaulter, attacker, crook, felon, malefactor, outlaw.

rapist (noun)	criminal (noun)
someone who forces another to have sexual intercourse	someone who has committed a crime or has been legally convicted of a crime

rapist (adjective)	criminal (adjective)
	guilty of crime or serious offense
	involving or being or having the nature of a crime
	bringing or deserving severe rebuke or censure