beholder vs actor

beholder and actor both are nouns.

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

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

beholder: a person who becomes aware (of things or events) through the senses
actor: a person who acts and gets things done

Other hypernyms of beholder include doer, worker.

beholder (noun)	actor (noun)
a person who becomes aware (of things or events) through the senses	a theatrical performer
	a person who acts and gets things done