second-rater vs actor

second-rater and actor both are nouns.

Word	Noun	Adjective	Verb	Adverb
second-rater	Yes	No	No	No
actor	Yes	No	No	No

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

Other hypernyms of second-rater include doer, worker.

second-rater (noun)	actor (noun)
a person of second-rate ability or value	a theatrical performer
	a person who acts and gets things done