yadda-yaddayoudaoicibaDictYouDict[yadda-yadda 词源字典]
"and so on," 1990s, of echoic origin (compare yatata "talk idly, chatter," 1940s; and yatter "to talk incessantly or idly," 1825).[yadda-yadda etymology, yadda-yadda origin, 英语词源]