madness vs mad

madness is a noun but mad is not a noun.

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

madness (noun)	mad (noun)
unrestrained excitement or enthusiasm
the quality of being rash and foolish
a feeling of intense anger
obsolete terms for legal insanity
an acute viral disease of the nervous system of warm-blooded animals (usually transmitted by the bite of a rabid animal); rabies is fatal if the virus reaches the brain

madness (adjective)	mad (adjective)
	roused to anger
	very foolish
	affected with madness or insanity
	marked by uncontrolled excitement or emotion