negate Meaning, Definition & Usage

1. verb be in contradiction with
   contradict; belie.
   
2. verb deny the truth of
   contradict; contravene.
   
3. verb prove negative; show to be false
   contradict.
   
4. verb make ineffective by counterbalancing the effect of
   nullify; neutralise; neutralize.
   
   • Her optimism neutralizes his gloom
   • This action will negate the effect of my efforts

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