Refute

impugnar

(to prove (something) to be false or incorrect)

negar la mayor

(to prove (something) to be false or incorrect)

negar rehusar

(to deny the truth or correctness of (something))

rebatir

(to prove (something) to be false or incorrect)

rechazar

(to deny the truth or correctness of (something))

refutar

(to prove (something) to be false or incorrect)

ripostar

(to prove (something) to be false or incorrect)

salir al paso de

(to prove (something) to be false or incorrect)