The overall idea we now have of the so-called “Western” dragon is the result of a stratified conflation of different traditions, and this process culminated in the Middle Ages, wherein traditional dragons, due to their innate serpentine quality, as well as common traits with the Leviathan of the Book of Job, began to be associated with the Biblical serpent — the one that tempted Eve to engage in the Original Sin.
Lo and Behold, dragons acquired some traits we now recognize them for, all associated with the iconography of the Devil: horns and bat-like wings, as well as the infamous dragon-fire, which is both an association to hell itself and an inheritance from the Biblical Leviathan.
Here be Dragons.
When a dragon in a fantasy work — be it a novel, a film, or a videogame — is depicted as having just two wings (often also locomotory limbs) and two legs, the argument is often made that “it is not a dragon; it has two wings and two legs, therefore it is a wyvern, and should not be called a dragon“. This belief of an absolute dragon-wyvern dichotomy is held by surprisingly many as a sort of dogmatic truth — one that is radically false, in the face of actual data, history, literature and classical art saying otherwise. Of course, in no way a completely arbitrary classification reflects the plasticity of the word dragon, as well as the concept(s) of dragon.
Allow me thus to take you readers into a flying journey through the fantastic and languages, and explain why dragons can have as many limbs and wings as they please and still be called dragons.