The giantess who became Njörðr’s wife and is associated with skiing is Skaði, commonly anglicized as Skadi.
Skaði is the daughter of the jötunn Þjazi. After the gods killed her father, they offered compensation, including marriage to one of them. She chose a husband by looking only at the candidates’ feet, hoping to select Baldr, but chose Njörðr instead. Their marriage was unhappy because Njörðr loved his sea-home Nóatún, while Skaði preferred her mountain home, Þrymheimr.
The Prose Edda says the couple tried alternating between the mountains and the coast, but neither could tolerate the other’s environment. Skaði is portrayed skiing, hunting with a bow, and living among the mountains; she is also linked with winter and snow.
She is sometimes confused with Jörð, the earth-associated figure and mother of Thor, or Rindr, another figure connected with Odin. Gríðr is a giantess who helps Thor, but she is not Njörðr’s wife. The surviving myths also differ on some details of Skaði’s later relationships.