extinction vs inaction

extinction and inaction both are nouns.

Word	Noun	Adjective	Verb	Adverb
extinction	Yes	No	No	No
inaction	Yes	No	No	No

As nouns, inaction is a hypernym of extinction; that is, inaction is a word with a broader meaning than extinction:

Other hypernyms of extinction include inactiveness, inactivity.

extinction (noun)	inaction (noun)
the act of extinguishing; causing to stop burning	the state of being inactive
a conditioning process in which the reinforcer is removed and a conditioned response becomes independent of the conditioned stimulus
complete annihilation
the reduction of the intensity of radiation as a consequence of absorption and radiation
no longer in existence
no longer active; extinguished