Continuing my look at some of the standard monsters of D&D, and continuing with the theme of the "evil tribal" races, it's time to turn to the gnolls - something that's particularly appropriate right now, given that they've recently been used as antagonists on Critical Role.
Although it has also been borrowed by other works, such as Terry Pratchett's Discworld novels, the term "gnoll" is not one that's native to folklore or legend. Gygax borrowed the word from a short fantasy story by Lord Dunsany, in which it is used to describe sinister woodland beings. Although Dunsany never described what his "gnoles" looked like, Gygax has stated that he took the word to mean that they were supposed to resemble a cross between a gnome and a troll, which is as plausible an etymology as any.
By the time of the 1E Monster Manual, however, he had already switched to the "hyena man" look that they have kept ever since. This appears to be original to D&D.