ability vs inability

ability and inability both are nouns.

Word	Noun	Adjective	Verb	Adverb
ability	Yes	No	No	No
inability	Yes	No	No	No

ability (noun)	inability (noun)
the quality of being able to perform; a quality that permits or facilitates achievement or accomplishment	lacking the power to perform
possession of the qualities (especially mental qualities) required to do something or get something done	lack of ability (especially mental ability) to do something