canard (n.)youdaoicibaDictYouDict[canard 词源字典]
before 1850, from French canard "a hoax," literally "a duck" (from Old French quanart, probably echoic of a duck's quack); said by Littré to be from the phrase vendre un canard à moitié "to half-sell a duck," thus, from some long-forgotten joke, "to cheat."[canard etymology, canard origin, 英语词源]