extra vs actor

extra and actor both are nouns.

Word	Noun	Adjective	Verb	Adverb
extra	Yes	Yes	No	Yes
actor	Yes	No	No	No

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

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

extra (noun)	actor (noun)
something additional of the same kind	a theatrical performer
an additional edition of a newspaper (usually to report a crisis)	a person who acts and gets things done
a minor actor in crowd scenes

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

extra (adverb)	actor (adverb)
unusually or exceptionally