1911 Encyclopædia Britannica/Canard

CANARD (the Fr. for “duck”), a sensational or extravagant story, a hoax or false report, especially one circulated by newspapers. This use of the word in France dates from the 17th century, and is supposed by Littré to have originated in the old expression, “vendre un canard à moitié” (to half-sell a duck); as it is impossible to “half-sell a duck,” the phrase came to signify to take in, or to cheat.