Main entry: vitiate, void, invalidate
Definition: take away the legal force of or render ineffective
Usage: invalidate a contract
Antonyms: validate
Definition: make valid or confirm the validity of
Main entry: nullify, invalidate
Definition: show to be invalid
Antonyms: validate
Definition: prove valid; show or confirm the validity of something
Main entry: void, avoid, annul, invalidate, nullify, quash
Definition: declare invalid
Usage: The contract was annulled; void a plea