raison d'etre vs role

raison d'etre and role both are nouns.

Word	Noun	Adjective	Verb	Adverb
raison d'etre	Yes	No	No	No
role	Yes	No	No	No

As nouns, role is a hypernym of raison d'etre; that is, role is a word with a broader meaning than raison d'etre:

Other hypernyms of raison d'etre include function, purpose, use.

raison d'etre (noun)	role (noun)
the purpose that justifies a thing's existence	the actions and activities assigned to or required or expected of a person or group
reason for being	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