knowledgeable vs knowledgeability

knowledgeable is not a noun while knowledgeability is a noun.

Word	Noun	Adjective	Verb	Adverb
knowledgeable	No	Yes	No	No
knowledgeability	Yes	No	No	No

knowledgeable (noun)	knowledgeability (noun)
	wisdom as evidenced by the possession of knowledge

knowledgeable (adjective)	knowledgeability (adjective)
highly educated; having extensive information or understanding
thoroughly acquainted through study or experience
alert and fully informed