klutz (n.)youdaoicibaDictYouDict[klutz 词源字典]
1967, American English, from Yiddish klots "clumsy person, blockhead," literally "block, lump," from Middle High German klotz "lump, ball." Compare German klotz "boor, clod," literally "wooden block" (see clot).[klutz etymology, klutz origin, 英语词源]