μύδρος

Etymology
If related to, which is formally proximate, this word originally denoted the molten, flowing metal mass as opposed to the hard iron. However, the technical meaning and the variant rather suggest a  origin.

Noun

 * 1) metal or iron mass roasted in fire
 * 2) anvil of stone or metal
 * 3) red hot iron in the hands, as an ordeal
 * 4) stone thrown out by a volcano, lapillus
 * 5) red hot stone throw in a liquid to vaporize it
 * 1) red hot stone throw in a liquid to vaporize it