Smeltery refuse is a term used to describe the waste materials produced during the smelting process. It consists of two components, DROSS (5 letters) and SLAG (4 letters). DROSS is a mixture of metal oxides and other impurities that form on the surface of molten metal, while SLAG is a non-metallic material that forms as a byproduct of the smelting process. Both DROSS and SLAG are considered smeltery refuse and must be disposed of properly.