n. (Math.) the property of a binary operation or operator such that the result of one term operating on a second is equal to the result of the second term operating on the first. [ GG ]

☞ If the symbol “*” is taken to be a commutative binary operator, then the following equation holds: a*b = b*a A common example is the addition operator for real numbers, “+”: a+b = b+a [ GG ]