senior vs actor

senior and actor both are nouns.

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

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

Other hypernyms of senior include doer, worker.

senior (noun)	actor (noun)
an undergraduate student during the year preceding graduation	a theatrical performer
a person who is older than you are	a person who acts and gets things done

senior (adjective)	actor (adjective)
older; higher in rank; longer in length of tenure or service
used of the fourth and final year in United States high school or college
advanced in years; (`aged' is pronounced as two syllables)