nullify   (Sound)

The verb nullify has 3 senses

• invalidate, annul, quash, void, avoid, nullify -- (declare invalid; "The contract was annulled"; "void a plea")


• invalidate, nullify -- (show to be invalid)


• neutralize, neutralise, nullify, negate -- (make ineffective by counterbalancing the effect of; "Her optimism neutralizes his gloom"; "This action will negate the effect of my efforts")