Official authorization, sanction, or warrant. Justification or valid grounds for an act or a course of action. Law An assurance by the seller of property that the goods or property are as represented or will be as promised. Law The insured's guarantee that the facts are as stated in reference to an insurance risk or that specified conditions will be fulfilled to keep the contract effective. Law A covenant by which the seller of land binds himself or herself and his or her heirs to defend the security of the estate conveyed. Law A judicial writ; a warrant. A guarantee given to the purchaser by a company stating that a product is reliable and free from known defects and that the seller will, without charge, repair or replace defective parts within a given time limit and under certain conditions.