peaky vs peak

peaky is not a noun while peak is a noun.

Word	Noun	Adjective	Verb	Adverb
peaky	No	Yes	No	No
peak	Yes	No	Yes	No

peaky (noun)	peak (noun)
	a brim that projects to the front to shade the eyes
	the top or extreme point of something (usually a mountain or hill)
	the highest point (of something)
	the most extreme possible amount or value
	a V shape
	the highest level or degree attainable; the highest stage of development
	the period of greatest prosperity or productivity

peaky (adjective)	peak (adjective)
having or as if having especially high-pitched spots

peaky (verb)	peak (verb)
	to reach the highest point; attain maximum intensity, activity