movie actor vs role player

movie actor and role player both are nouns.

Word	Noun	Adjective	Verb	Adverb
movie actor	Yes	No	No	No
role player	Yes	No	No	No

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

Other hypernyms of movie actor include actor, histrion, player, thespian.

movie actor (noun)	role player (noun)
an actor who plays a role in a film	a theatrical performer
	a person who makes deceitful pretenses