handicapped vs unfit

handicapped is a noun but unfit is not a noun.

Word	Noun	Adjective	Verb	Adverb
handicapped	Yes	Yes	No	No
unfit	No	Yes	Yes	No

handicapped (noun)	unfit (noun)
people collectively who are crippled or otherwise physically handicapped

handicapped (adjective)	unfit (adjective)
the total or partial absence of a person's bodily or mental functions, including the absence of a part of a person's body	not in good physical or mental condition; out of condition
	below the required standards for a purpose
	physically unsound or diseased

handicapped (verb)	unfit (verb)
	make unfit or unsuitable