aftermath vs backwash

aftermath and backwash both are nouns.

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

As nouns, aftermath and backwash are synonyms defined as:

aftermath and backwash: the consequences of an event (especially a catastrophic event)

Other synonyms of aftermath include wake.

aftermath (noun)	backwash (noun)
the outcome of an event especially as relative to an individual	the wave that spreads behind a boat as it moves forward
the consequences of an event (especially a catastrophic event)	the flow of air that is driven backwards by an aircraft propeller
	the consequences of an event (especially a catastrophic event)