What for what; something for something. Used in law for the giving one valuable thing for another. It is nothing more than the mutual consideration which passes between the parties to a contract, and which renders it valid and binding. Cowell. Quid sit jus, et in quo consistit injuria, legis est definire. What constitutes right, and what injury, it is the business of the law to declare. Co. Litt. 15S6.