nullify meaning and definition

NULLIFY verb

Definition of nullify (verb)

1. declare invalid
   • "The contract was annulled"; "void a plea"
   • synonyms: annul, avoid, invalidate, quash, void
   • antonym: formalise
2. show to be invalid
   • synonyms: invalidate
   • antonym: validate
3. make ineffective by counterbalancing the effect of
   • "Her optimism neutralizes his gloom"; "This action will negate the effect of my efforts"
   • synonyms: negate, neutralise, neutralize