extra vs role player

extra and role player both are nouns.

Word	Noun	Adjective	Verb	Adverb
extra	Yes	Yes	No	Yes
role player	Yes	No	No	No

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

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

extra (noun)	role player (noun)
something additional of the same kind	a theatrical performer
an additional edition of a newspaper (usually to report a crisis)	a person who makes deceitful pretenses
a minor actor in crowd scenes

extra (adjective)	role player (adjective)
further or added
more than is needed, desired, or required
added to a regular schedule

extra (adverb)	role player (adverb)
unusually or exceptionally