annul
verb [ T ] law specialized uk/əˈnʌl/ us/əˈnʌl/ -ll-
废除，取消（法律、协议等）;宣布（婚姻）无效
to officially announce that something such as a law, agreement, or marriage no longer exists
His second marriage was annulled because he never divorced his first wife. 他的第二次婚姻被判无效，因为他从未与第一任妻子离婚。