What is the meaning of invalidating?

verb

• Declare invalid.
  • usage: "The contract was annulled"; "void a plea"
  • synonyms: invalidate, annul, quash, void, avoid, nullify
• Make invalid for use.
  • usage: "cancel cheques or tickets"
  • synonyms: cancel, invalidate
• Show to be invalid.
  • synonyms: invalidate, nullify
• Take away the legal force of or render ineffective.
  • usage: "invalidate a contract"
  • synonyms: invalidate, void, vitiate

adjective

• Establishing as invalid or untrue.
  • synonyms: disconfirming