Brock is a word for a badger or a badger's den.
It is also the name of an important dwarf in Norse mythology.
After Loki cut off Sif's hair, he went to the dark elves - the Svartalfar - and got them to make hair of gold, the ship Skidbladnir, and the spear Gungnir.
He then went to Brock, a dwarf, and bet his head that Brock's brother the smith (sometimes called Sindri, sometimes Eitri) couldn't make three superior artifacts.
Brock worked the bellows while his brother forged the magical items; Gullinbrusti, the golden boar given to Frey, the ring Draupnir, and the hammer Mjollnir. But during the forging of Mjollnir, a fly bit Brock on the forehead, which made him stop working the bellows for an instant, and the hammer was marred slightly.
The Aesir judged Mjollnir to be better than the other gifts, so Brock demanded Loki's head. Loki argued that he could have the head, but couldn't touch his neck; frustrated, Brock sewed Loki's lips together to shut him up.
I think that Brock and his brother also forged the chain named Gleipnir, that bound Fenris.