destiny vs inevitable

destiny and inevitable both are nouns.

Word	Noun	Adjective	Verb	Adverb
destiny	Yes	No	No	No
inevitable	Yes	Yes	No	No

As nouns, inevitable is a hyponym of destiny; that is, inevitable is a word with a more specific, narrower meaning than destiny:

destiny: an event (or a course of events) that will inevitably happen in the future
inevitable: an unavoidable event

Other hyponyms of destiny include karma, kismat, kismet, predestination, day of reckoning, doom, doomsday, end of the world.

destiny (noun)	inevitable (noun)
an event (or a course of events) that will inevitably happen in the future	an unavoidable event
the ultimate agency regarded as predetermining the course of events
your overall circumstances or condition in life (including everything that happens to you)

destiny (adjective)	inevitable (adjective)
	incapable of being avoided or prevented
	invariably occurring or appearing