commutateyoudaoicibaDictYouDict[commutate 词源字典]
"Regulate or reverse the direction of (an alternating electric current), especially to make it a direct current", Late 19th century: from Latin commutat- 'changed altogether, exchanged, interchanged', from the verb commutare (see commute).[commutate etymology, commutate origin, 英语词源]