causal agent vs destiny

causal agent and destiny both are nouns.

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

As nouns, destiny is a hyponym of causal agent; that is, destiny 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
destiny: the ultimate agency regarded as predetermining the course of events

causal agent (noun)	destiny (noun)
any entity that produces an effect or is responsible for events or results	an event (or a course of events) that will inevitably happen in the future
	the ultimate agency regarded as predetermining the course of events
	your overall circumstances or condition in life (including everything that happens to you)