invalidate meaning and definition

INVALIDATE verb

Definition of invalidate (verb)

1. declare invalid
   • "The contract was annulled"; "void a plea"
   • synonyms: annul, avoid, nullify, quash, void
   • antonym: formalise
2. make invalid for use
   • "cancel cheques or tickets"
   • synonyms: cancel
3. show to be invalid
   • synonyms: nullify
   • antonym: validate
4. take away the legal force of or render ineffective
   • "invalidate a contract"
   • synonyms: vitiate, void
   • antonym: validate