What is Adequate Consideration?

Legal Definition
One which is equal, or reasonably proportioned, to the value of that for which it is given. 1 Story, Eq. Jur. §§ 244-247. An adequate consideration is one which is not so disproportionate as to shock our sense of that morality and fair dealing which should always characterize transactions between man and man. Eaton v. Patterson, 2 Stew. & P. (Ala.) 9, 19.
-- Black's Law Dictionary