dross vs sullage

dross

noun
  • Residue that forms on the surface of molten metal from oxidation. 

  • Worthless or trivial matter. 

  • The impurities in metal. 

  • Waste or impure matter. 

  • A waste product from working with metal. 

verb
  • To remove dross from. 

sullage

noun
  • The scoria on the surface of molten metal in the ladle. 

  • Silt or sediment deposited from flowing water. 

  • That which sullies or defiles. 

  • The liquid discharges from kitchens, washbasins, toilets etc; sewage. 

How often have the words dross and sullage occurred in a corpus of books? (source: Google Ngram Viewer )