1. In Mathematics, it is a number or other known factor, typically a constant, by which another number or factor, typically a variable, is multiplied. For example, in the equation ax2 + bx + c = 0, ‘a’ is the coefficient of x2 and ‘b’ is the coefficient of x. 2. In Physics and statistics, it is the measure under specified conditions of a specified characteristic or property of a particular object, body, material, phenomenon, or procedure.