An Etymological Dictionary of the German Language/Daus
Daus, n., ‘deuce (of dice), ace (of cards),’ from MidHG. dûs, tûs, with the same meanings; late OHG. dûs. From a Rom. word originating in the Lat. duo; OFr. dous (ModFr. deux, Prov. duas, from Lat. *duos for duo), whence E. deuce. Dice-playiug was a favourite amusement even among the Teutons described by Tacitus (Germ. 24); unfortunately, however, we can gather nothing from his brief remarks as to the details and technical terms (but see gefallen, Hund, Sau) of the OTeut. game; this words died out at an early period, and with the new games from the South new Rom. words have been introduced. See Aß, Treff, doppeln.