v.使无效；废除；取消
The election results were nullified because of voter fraud. 因为选民舞弊，选举结果无效。
Counterintelligence seeks to nullify the enemy's espionage efforts. 反间谍情报之目的是挫败敌人的间谍活动。
He has no right to nullify laws. 他无权废除法律。
An unhealthy diet will nullify the effects of training. 不健康的饮食会抵消锻炼的效果。
