departure vs variant

departure and variant both are nouns.

Word	Noun	Adjective	Verb	Adverb
departure	Yes	No	No	No
variant	Yes	Yes	No	No

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

Other hyponyms of departure include discrepancy, variance, driftage, flection, flexion, inflection.

departure (noun)	variant (noun)
the act of departing	a variable quantity that is random
euphemistic expressions for death	something a little different from others of the same type
a variation that deviates from the standard or norm	an event that departs from expectations
	(biology) a group of organisms within a species that differ in trivial ways from similar groups

departure (adjective)	variant (adjective)
	differing from a norm or standard
	exhibiting variation and change