ability vs able

ability is a noun but able is not a noun.

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

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

ability (adjective)	able (adjective)
	(usually followed by `to') having the necessary means or skill or know-how or authority to do something
	having inherent physical or mental ability or capacity
	have the skills and qualifications to do things well
	having a strong healthy body