Thor's hammer

In Norse mythology, Mjölnir (Old Norse: Mjǫllnir, IPA: [ˈmjɔlːnir]) is the hammer of Thor, a major Norse god associated with thunder. Mjölnir is depicted in Norse mythology as one of the most fearsome weapons, capable of leveling mountains. In his account of Norse mythology, Snorri Sturluson relates how the hammer was made by the dwarven brothers Sindri and Brokkr, and how its characteristically short handle was due to a mishap during its manufacture. Similar hammers (Ukonvasara) were a common symbol of the god of thunder in other North European mythologies.

Old Norse Mjǫllnir /ˈmjɔlːnir/ regularly becomes Mjøllnir /ˈmjœlːnir/ in Old Icelandic by the 13th century. The modern Icelandic form is Mjölnir, Norwegian and Danish Mjølner, Swedish Mjölner.

The name is derived from a Proto-Germanic form *meldunjaz, from the Germanic root of "to grind" (, Old Icelandic meldr, mjǫll, mjǫl "meal, flour"), yielding an interpretation of "the grinder; crusher".

Additionally, there is a suggestion that the mythological "thunder weapon" being named after the word for "grindstone" is of considerable, Proto-Indo-European (if not Indo-Hittite) age; according to this suggestion, the divine thunder weapon (identified with lightning) of the storm god was imagined as a grindstone (Russian and possibly Hittite malatt- "sledgehammer, bludgeon"), reflected in Russian молния (molniya) and Welsh mellt "lightning" (possibly cognate with Old Norse mjuln "fire").

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