verb
contradict
kahn-truh-DIKT/ˌkɑːntrəˈdɪkt/
To say or show the opposite of what is claimed or expected.
The woman contradicts the man's description of sunshine by insisting it is raining.

Etymology
The pieces mean “speak against”: to contradict people is to oppose their words with a statement asserting the opposite, rather than merely speaking against them in a general way.
In context
Well, maybe she's right. I don't know. I'm not going to contradict her.
More examples
- Her actions contradict her promise to treat everyone fairly.
- The witness contradicted himself during the interview.
- These results contradict our expectations.
Forms
contradict · contradicts · contradicted · contradicting
contradiction noun — A statement or fact expressing the opposite.
contradictory adjective — Expressing opposing claims or incompatible facts.