The name occurs in the 11th stanza of the Völuspá:
Nýi, Niði, Norðri, Suðri,
Austri, Vestri, Alþjófr, Dvalinn,
Nár ok Náinn, Nípingr, Dáinn,
Bifurr, Bafurr, Bömburr, Nori,
Ánn ok Ánarr, Óinn, Mjöðvitnir.
Bellows translates it thus:
Nyi and Nithi, | Northri and Suthri,
Austri and Vestri, | Althjof, Dvalin,
Nar and Nain, | Niping, Dain,
Bifur, Bofur, | Bombur, Nori,
An and Onar, | Ai, Mjothvitnir.
A list of proper names. Names of Dwarves. Most of them have litteral meaning, including Mioðvitnir, which means "Mead-Wolf." Team mates ignore why Mioðvitnir has a Dwarf name. Only why he bears a Wolf name.