(1):

(v. i.) To oppose in words; to gainsay; to deny, or assert the contrary of, something.

(2):

(v. t.) To assert the contrary of; to oppose in words; to take issue with; to gainsay; to deny the truth of, as of a statement or a speaker; to impugn.

(3):

(v. t.) To be contrary to; to oppose; to resist.