köken: An originally Central and Low German word from Middle Low German mül (“dust”) and Middle High German mülle, from Old High German mulli (“waste, rubbish”), a nominal formation from mullen (“to crush, grind”), from Proto-Germanic *muljaną (“to crush”) (DWDS).
köken: From Low German slagge, slakke, from Middle Low German slagge, perhaps from slagen (“to strike”), from Old Saxon slegi, from Proto-West Germanic *slagi.