wyvern
A draconian creature possessing wings, only two legs and usually a barbed tail.
[I]f (notwithstanding his obligations to the three ermines passant) he sometimes cursed in his heart the jargon of heraldry, its griffins, its moldwarps, its wyverns, and its dragons, with all the bitterness of Hotspur himself, there were moments when these communications interested his fancy and rewarded his attention.
Where it comes from
Alteration of Middle English wyver (“viper”), from Old Northern French wivre, from Vulgar Latin *vivra, *vibra, from Latin vīpera (“viper; snake, serpent”). Doublet of weever and viper. Related to viviparous.
Adapted from the Wiktionary entry wyvern (CC BY-SA 4.0).