perceptive vs acute

perceptive is not a noun while acute is a noun.

Word	Noun	Adjective	Verb	Adverb
perceptive	No	Yes	No	No
acute	Yes	Yes	No	No

perceptive (noun)	acute (noun)
	a mark placed above a vowel to indicate pronunciation

perceptive (adjective)	acute (adjective)
having the ability to perceive or understand; keen in discernment	having or experiencing a rapid onset and short but severe course
of or relating to perception	of an angle; less than 90 degrees
	of critical importance and consequence
	having or demonstrating ability to recognize or draw fine distinctions
	ending in a sharp point
	extremely sharp or severe