In Norse mythology, Níðhöggr is the dragon said to gnaw the corpses of the dead in Náströnd.
Níðhöggr appears in the Poetic Edda, especially in Völuspá, a poem describing the creation, destruction, and renewal of the cosmos. The creature is associated with the roots of Yggdrasil, the world tree, and with the grim regions beneath or beyond the human world. In accounts of Náströnd, the dead are punished while Níðhöggr feeds on their bodies.
Níðhöggr is often translated as “Malice Striker” or “Dread Biter,” although translations vary because Old Norse compounds can be interpreted in more than one way. The dragon is not the same as Jörmungandr, the Midgard Serpent, or Fafnir, the dragon defeated by the hero Sigurd. Garmr, meanwhile, is a separate doglike guardian associated with the underworld.
Völuspá also describes Níðhöggr flying with corpses after Ragnarök, linking the creature to both the underworld and the world’s final transformation.