dross

From Middle English drosse, dros, from Old English drōs, from Proto-Germanic *drōhs (“dregs, sediment”). Also compare Old English drōsna, drōsne (“a ground, sediment, lees, dregs, dirt, ear wax”), from Proto-Germanic drōhsnǭ, drōhsnō (“dregs, sediment”), derived from drōhs. Alternatively, this may be from dragjō + -snō (“yeast, sediment”; compare dragjō (“yeast”)), as if from *drēcg + -sn. Ultimately from Proto-Indo-European *dʰrā́ks (“sediment, yeast”). Cognate with Scots dros, drose, drosse (“small particles, fragments, dross”), Middle Dutch droes (“dregs”), Dutch droesem (“dregs”), German Drusen (“lees, dregs”), Latin fracēs (“grounds or dregs of oil”). Related also to drast, dregs.