knower vs actor

knower and actor both are nouns.

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

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

Other hypernyms of knower include doer, worker.

knower (noun)	actor (noun)
a person who knows or apprehends	a theatrical performer
	a person who acts and gets things done