1. (

• invalidate ,
• annul ,
• quash ,
• void ,
• avoid ,
• nullify

) declare invalid; "The contract was annulled"; "void a plea" ;

2. (

• revoke ,
• annul ,
• lift ,
• countermand ,
• reverse ,
• repeal ,
• overturn ,
• rescind ,
• vacate

) cancel officially; "He revoked the ban on smoking"; "lift an embargo"; "vacate a death sentence" ;