exception vs exceptional

exception is a noun but exceptional is not a noun.

Word	Noun	Adjective	Verb	Adverb
exception	Yes	No	No	No
exceptional	No	Yes	No	No

exception (noun)	exceptional (noun)
a deliberate act of omission
an instance that does not conform to a rule or generalization
grounds for adverse criticism

exception (adjective)	exceptional (adjective)
	deviating widely from a norm of physical or mental ability; used especially of children below normal in intelligence
	far beyond what is usual in magnitude or degree
	surpassing what is common or usual or expected