invalidate

英 [ɪn'vælɪdeɪt] 美[ɪn'vælɪdet]

• vt. 使无效；使无价值

1. declare invalid;

"The contract was annulled"

"void a plea"

2. of cheques or tickets

3. show to be invalid

4. take away the legal force of or render ineffective;

"invalidateas a contract"