An act, forbearance, or promise by one party to a contract that constitutes the price for which he buys the promise of the other. When, at the desire of the promisor, the promise or any other person has done or abstained from doing, or does or abstains from doing, or promises to do or to abstain from doing, something, such act or abstinence or promise is called a consideration for the promise. [Section 2(d) of the Contact Act, 1872]