impair vs impairment

impair is not a noun while impairment is a noun.

Word	Noun	Adjective	Verb	Adverb
impair	No	No	Yes	No
impairment	Yes	No	No	No

impair (noun)	impairment (noun)
	damage that results in a reduction of strength or quality
	the act of making something futile and useless (as by routine)
	the occurrence of a change for the worse
	the condition of being unable to perform as a consequence of physical or mental unfitness
	a symptom of reduced quality or strength

impair (verb)	impairment (verb)
make worse or less effective
make imperfect