Contradict (verb)

1. To say or assert the opposite of (something previously said); deny or oppose.
2. To be in opposition or disagreement with; be incompatible with.

Origin:

From latin contradicere "speak against", from contra- "against" + dicere "to speak".

Examples:

1. He contradicted the statement made by the witness.
2. The evidence contradicts the defendant's alibi.
3. The theory contradicts the known facts.
4. The statement contradicts the previous testimony.
5. The evidence contradicts the prosecution's argument.