logical system vs negate

logical system is a noun but negate is not a noun.

Word	Noun	Adjective	Verb	Adverb
logical system	Yes	No	No	No
negate	No	No	Yes	No

logical system (noun)	negate (noun)
a system of reasoning

logical system (verb)	negate (verb)
	make ineffective by counterbalancing the effect of
	prove negative; show to be false
	deny the truth of
	be in contradiction with