title role vs role

title role and role both are nouns.

Word	Noun	Adjective	Verb	Adverb
title role	Yes	No	No	No
role	Yes	No	No	No

As nouns, role is a hypernym of title role; that is, role is a word with a broader meaning than title role:

Other hypernyms of title role include character, part, persona, theatrical role.

title role (noun)	role (noun)
the role of the character after whom the play is named	the actions and activities assigned to or required or expected of a person or group
	normal or customary activity of a person in a particular social setting
	what something is used for
	an actor's portrayal of someone in a play