crazy vs mad

crazy is a noun but mad is not a noun.

Word	Noun	Adjective	Verb	Adverb
crazy	Yes	Yes	No	No
mad	No	Yes	No	No

As adjectives, crazy and mad are synonyms defined as:

Other synonyms of crazy include brainsick, demented, disturbed, sick, unbalanced, unhinged.

crazy (noun)	mad (noun)
someone deranged and possibly dangerous

crazy (adjective)	mad (adjective)
intensely enthusiastic about or preoccupied with	roused to anger
possessed by inordinate excitement	very foolish
foolish; totally unsound	affected with madness or insanity
affected with madness or insanity	marked by uncontrolled excitement or emotion
bizarre or fantastic