Coefficient
A constant multiplier of a variable is known as coefficient. They are typically represented by letters a,b,c.
Example:
In the expression 3x+5,3 is the coefficient of x.
In the equation 4x+2y=6,4 is the coefficient of x and 2 is the coefficient of y.
In the inequality 2*sin(x)+3>z,2 is the coefficient of the function sin(x).