negate vs contravene

negate and contravene both are verbs.

Word	Noun	Adjective	Verb	Adverb
negate	No	No	Yes	No
contravene	No	No	Yes	No

As verbs, negate and contravene are synonyms defined as:

Other synonyms of negate include contradict.

negate (verb)	contravene (verb)
make ineffective by counterbalancing the effect of	deny the truth of
prove negative; show to be false	go against, as of rules and laws
deny the truth of
be in contradiction with