An Etymological Dictionary of the German Language/Zauber
Zauber, m., ‘charm, enchantment, magic,’ from MidHG. zouber (zouver), OHG. zoubar (zoufar), m., ‘magic, charm, spell’; comp. Du. tooveren, ‘to enchant,’ OIc. taufr, n., ‘magic.’ For the meaning, the corresponding AS. teáfor, ‘vermilion,’ is important; hence Zauber is perhaps lit. ‘illusion by means of colour’; others suppose that the runes were marked with vermilion, so that Zauber would mean lit. ‘secret or magic writing.’ No cognates of the specifically Teut. taufro-, taubro- (Aryan root dū̆p, not dū̆bh), have been found.