1530s, from Medieval Latin commutativus, from Latin commutat-, past participle stem of commutare (see commute (v.)).
commutative (kə-my'tə-tĭv, kŏm'yə-tā'tĭv) Of or relating to binary operations for which changing the order of the inputs does not change the result of the operation. For example, addition is commutative, since a + b = b + a for any two numbers a and b, while subtraction is not commutative, since a - b ` a - b unless both a and b are zero. See also associative, distributive. |