resultant vs aftermath

resultant and aftermath both are nouns.

Word	Noun	Adjective	Verb	Adverb
resultant	Yes	Yes	No	No
aftermath	Yes	No	No	No

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

Other hyponyms of resultant include denouement, deal, decision, decision, consequence, separation, sequel, subsequence, worst.

resultant (noun)	aftermath (noun)
a vector that is the sum of two or more other vectors	the outcome of an event especially as relative to an individual
something that results	the consequences of an event (especially a catastrophic event)
the final point in a process

resultant (adjective)	aftermath (adjective)
occurring with or following as a consequence