backwash vs consequence

backwash and consequence both are nouns.

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

As nouns, consequence is a hypernym of backwash; that is, consequence is a word with a broader meaning than backwash:

backwash: the consequences of an event (especially a catastrophic event)
consequence: a phenomenon that follows and is caused by some previous phenomenon

Other hypernyms of backwash include effect, event, issue, outcome, result, upshot.

backwash (noun)	consequence (noun)
the wave that spreads behind a boat as it moves forward	having important effects or influence
the flow of air that is driven backwards by an aircraft propeller	the outcome of an event especially as relative to an individual
the consequences of an event (especially a catastrophic event)	a phenomenon that follows and is caused by some previous phenomenon