Waste material is any unwanted or unusable material that is discarded or left over from a process. SLAG, which is four letters long, is a by-product of smelting ore that is usually discarded as waste. RUBBISH, seven letters long, is a term used to describe any unwanted or discarded material, such as paper, plastic, or glass. SEWAGE, six letters long, is the wastewater that is produced by households and industries. SCRAP, five letters long, is any material that is leftover from a manufacturing process. LITTER, six letters long, is any type of TRASH or DEBRIS that is left in an outdoor area. TRASH, five letters long, is another term for garbage or refuse. DROSS, five letters long, is the impurities that are left over after a metal has been melted. DEBRIS, six letters long, is any type of broken or fragmented material that is left over from a construction or demolition project.