Specifically, this compound uses røkkr , meaning "twilight" or "darkness". This form was likely popularized by later poets and scholars, such as those who wrote the Prose Edda , to create a dramatic, aesthetic image of the end—similar to the Wagnerian "Twilight of the Gods" (Götterdämmerung).
Odin, the All-Father, is devoured by the wolf Fenrir. røkkr