abatement vs mitigation

abatement and mitigation both are nouns.

Word	Noun	Adjective	Verb	Adverb
abatement	Yes	No	No	No
mitigation	Yes	No	No	No

As nouns, mitigation is a hypernym of abatement; that is, mitigation is a word with a broader meaning than abatement:

Other hypernyms of abatement include moderation.

abatement (noun)	mitigation (noun)
the act of abating	to act in such a way as to cause an offense to seem less serious
an interruption in the intensity or amount of something	the action of lessening in severity or intensity
	a partial excuse to mitigate censure; an attempt to represent an offense as less serious than it appears by showing mitigating circumstances