Ymir is a primordial being in Norse mythology, often referred to as the progenitor of the cosmos and all life within it. According to the Prose Edda, written by Snorri Sturluson, Ymir was a giant born from the meeting of the fiery realm of Muspelheim and the icy void of Niflheim. From Ymir's body, the gods created the world: his flesh became the earth, his blood the seas, his bones the mountains, and his skull the sky. The translation of Ymir to Hebrew is ימאיר (Yamir). In Old Norse, the term is Ýmir, which may be derived from the word yr, meaning "yogurt" or "sour milk," possibly referring to the primordial substance from which Ymir emerged. Ymir's death at the hands of the god Odin and his brothers marked the beginning of the creation of the world as known in Norse cosmology. Ymir's descendants, the Jötnar (giants), are central figures in many Norse myths, often in conflict with the gods.