character actor vs thespian

character actor and thespian both are nouns.

Word	Noun	Adjective	Verb	Adverb
character actor	Yes	No	No	No
thespian	Yes	Yes	No	No

As nouns, thespian is a hypernym of character actor; that is, thespian is a word with a broader meaning than character actor:

Other hypernyms of character actor include actor, histrion, player, role player.

character actor (noun)	thespian (noun)
an actor who specializes in playing supporting roles	a theatrical performer

character actor (adjective)	thespian (adjective)
	of or relating to drama