Alduin, aslo known as the World Eater also considered an alternative name of Akatosh (patron god of dragons and time) by some of Tamriel is a dragon and the primary antagonist of The Elder Scrolls V: Skyrim's Main Quest. He is considered the "wellspring" of the Nordic pantheon, as well as the harbinger of the apocalypse. He is also described as the "creator of dragon civilization" in one particular text.
In the Dragon Language his name is spelled using the words for Destroyer/AL, Devour/DU, and Master/IN.
Many dragons refer to Alduin as "the first" while a few even call him Brother. Alduin himself as even called them his children, however the actual familial connection is up for debate.