In Norse mythology, Angrboða (Old Norse "the one who brings grief" or "she-who-offers-sorrow") is a female jötunn (giantess). In the Poetic Edda, Angrboða is mentioned only in Völuspá hin skamma (found in Hyndluljóð) as the mother of Fenrir by Loki. However, in the Prose Edda book Gylfaginning, she is referred to as a "giantess in Jötunheimr" and said also to be the mother of Fenrir's siblings Jörmungandr (the Midgard Serpent) and Hel. She may be identical with Iárnvidia, 'She of Iron-wood', mentioned in the list of troll-wives in the Prose Edda list nafnaþulur.
The poem Völuspá (stanzas 40–41 in most editions) speaks of a giantess dwelling in Járnvid ('Iron-wood') whom commentators usually identify with Angrboða (and the Iárnvidia of the list of troll-wives):
The giantess old in Ironwood sat,
In the east, and bore the brood of Fenrir;
Among these one in monster's guise
Was soon to steal the sun from the sky.
There feeds he full on the flesh of the dead,
And the home of the gods he reddens with gore;
Dark grows the sun, and in summer soon
Snorri's Gylfaginning gives a prose explanation and a variant form of these stanzas. Brodeur's translation renders:
A witch dwells to the east of Midgard, in the forest called Ironwood: in that wood dwell the troll-women, who are known as Ironwood-Women [Iárnvidjur]. The old witch bears many giants for sons, and all in the shape of wolves; and from this source are these wolves sprung. The saying runs thus: from this race shall come one that shall be mightiest of all, he that is named Moon-Hound [Mánagarm]; he shall be filled with the flesh of all those men that die, and he shall swallow the moon, and sprinkle with blood the heavens and all the lair; thereof-shall the sun lose her shining, and the winds in that day shall be unquiet and roar on every side. So it says in Völuspá: