understanding vs perceptive

understanding is a noun but perceptive is not a noun.

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

understanding (noun)	perceptive (noun)
the capacity for rational thought or inference or discrimination
the cognitive condition of someone who understands
an inclination to support or be loyal to or to agree with an opinion
the statement (oral or written) of an exchange of promises

understanding (adjective)	perceptive (adjective)
characterized by understanding based on comprehension and discernment and empathy	having the ability to perceive or understand; keen in discernment
	of or relating to perception