In the feminine form, an alternative name for Jörð, the mother of Thor. She is first mentioned as such in a stanza from Völuspá, which predicts Thor's death:
Nine feet will go Fiörgyn's son, bowed by the serpent, who feared no foe. The second occurrence is in a stanza from Hárbarðsljóð:
... then keep the left hand way, until thou reachest Verland; there will Fjörgyn find her son Thor, and point out to him his kinsmen's ways to Odin's land.
In the masculine form (Fjörgynn or Fjörgvinn), it is an alternative name of the father of Frigg. It is found in Lokasenna and in Snorri Sturluson's Prose Edda, in both Gylfaginning and Skáldskaparmál. A valid kenning for Frigg is Daughter of Fjörgynn.
- Gylfaginning, 9.
- Hárbarðsljóð, 56.
- Lokasenna, 26.
- Skáldskaparmál, 19.
- Völuspá, 55.