In Norse mythology, Hymir is a giant, husband of the giantess Hroðr and according to the Eddic poem Hymiskviða the father of the god Týr (in other sources, Odin is Tyr's father and Hymir his maternal-grandfather -- but all sources agree that Tyr and Hymir are related). He is the owner of a mile-wide cauldron in which the Æsir wanted to brew beer; Thor, accompanied by Týr, obtained it from him. He has several daughters.
Hymiskviða and Gylfaginning
Hymiskviða recounts how Thor and Týr obtain the cauldron from Hymir. His skull is unusually hard, and Thor breaks a cup by throwing it at Hymir's head.
Hymiskviða also recounts Thor's fishing for Jörmungandr, the Midgard serpent. Thor goes fishing with Hymir, using the head of Hymir's best ox for bait, and catches Jörmungandr, who then either breaks loose or, as told in the Gylfaginning of the Prose Edda, is cut loose by Hymir. The Prose Edda provides the additional detail that while Thor was attempting to pull Jörmungandr in, his feet went through the bottom of the boat.
This encounter between Thor and Jörmungandr seems to have been one of the most popular motifs in Norse art. Three picture stones have been linked with the story and show Hymir: the Ardre VIII image stone, the Hørdum stone, and the Gosforth Cross. A stone slab that may be a portion of a second cross at Gosforth also shows a fishing scene using an ox head for bait. The legend is also depicted on the Altuna Runestone, but its image does not show Hymir, possibly due to the narrow shape of that stone.