exceptional vs psychology

exceptional is not a noun while psychology is a noun.

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

exceptional (noun)	psychology (noun)
	the science of mental life

exceptional (adjective)	psychology (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