causal agent vs actor

causal agent and actor both are nouns.

Word	Noun	Adjective	Verb	Adverb
causal agent	Yes	No	No	No
actor	Yes	No	No	No

As nouns, actor is a hyponym of causal agent; that is, actor is a word with a more specific, narrower meaning than causal agent:

causal agent: any entity that produces an effect or is responsible for events or results
actor: a person who acts and gets things done

causal agent (noun)	actor (noun)
any entity that produces an effect or is responsible for events or results	a theatrical performer
	a person who acts and gets things done