An Etymological Dictionary of the German Language/Becher
Becher, m., ‘beaker, goblet,’ from the equiv. MidHG. bëcher, OHG. bëhhar, bëhhâri, m.; comp. OLG. bikeri, Du. beker, OIc. bikarr, whence MidE. biker, E. beaker. These cognates are derived from LowLat. bicarium, allied to Lat. bacar (‘vas vinarium,’ according to Festus), and still appearing in Ital. bicchiere. The Lat. word was naturalised in Germany perhaps as far back as the 7th cent., probably at the same period as Kelch, since its c was changed into hh, ch.