Oxford English Dictionary 1a. A mutual agreement between two or more parties that something shall be done or forborne by one or both; a compact, covenant, bargain; esp. such as has legal effects (see 2); a convention between states.
b. esp. A business agreement for the supply of certain articles or the performance of specified work at a certain price, rate, or commission.
d. ‘A writing in which the terms of a bargain are included’ (Johnson).