quickest vs quick

quickest is not a noun while quick is a noun.

Word	Noun	Adjective	Verb	Adverb
quickest	No	No	No	Yes
quick	Yes	Yes	No	Yes

quickest (noun)	quick (noun)
	any area of the body that is highly sensitive to pain (as the flesh underneath the skin or a fingernail or toenail)

quickest (adjective)	quick (adjective)
	moving quickly and lightly
	easily aroused or excited
	accomplished rapidly and without delay
	hurried and brief
	apprehending and responding with speed and sensitivity
	performed with little or no delay

quickest (adverb)	quick (adverb)
most quickly	with little or no delay