Synonyms for nullify

Verb

1. invalidate, annul, quash, void, avoid, nullify, cancel, strike down

usage: declare invalid; "The contract was annulled"; "void a plea"

2. invalidate, nullify, negate, contradict

usage: show to be invalid

3. neutralize, neutralise, nullify, negate, weaken

usage: make ineffective by counterbalancing the effect of; "Her optimism neutralizes his gloom"; "This action will negate the effect of my efforts"