invalidate

To make invalid; nullify.

To render invalid; destroy the strength or validity of; render of no force or effect.

Specifically In law, to deprive of binding force or legal efficacy: as, fraud invalidates a contract.

To render invalid; to weaken or lessen the force of; to destroy the authority of; to render of no force or effect; to overthrow.

To make invalid. Esp. applied to contract law.

show to be invalid

take away the legal force of or render ineffective

declare invalid

make invalid for use