negate
/nɪˈɡeɪt/verb
To declare that something is not true or does not exist; to contradict it.
Example sentences
- “The new evidence negates the theory the police had been working on.”
- “One careless remark can negate months of goodwill.”
In grammar, 'not' negates a sentence; in formal writing, one thing can negate the effect of another.