1909 in the figurative sense of "complete overthrow" of something; from German Gtterdmmerung (18c.), literally "twilight of the gods," from genitive plural of Gott "god" (see god) + Dmmerung "dusk, twilight," from PIE root *teme- "dark" (see temerity). Used by Wagner as the title of the last opera in the Ring cycle. It translates Old Norse ragna rok "the doom or destruction of the gods, the last day, world's end." Used by Wagner as the title of the last opera in the Ring cycle.