screen actor vs role player

screen actor and role player both are nouns.

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

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

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

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