An Etymological Dictionary of the German Language/Reis
Reis (1.), m., ‘rice,’ from the equiv. MidHG. rîs, m. and n., which was borrowed from the equiv. MidLat. and Rom. rîso-, m. and n,; comp. Ital. riso, Fr. riz (whence also E. rice, Du. rijst); the latter is usually traced to Lat. and Gr. ὄρῦζον (also ὄρυζα), ‘rice,’ which is derived from Sans. vrîhi through an Iran. medium.
Reis (2.), ‘twig, sprout,’ from MidHG. rîs, OHG. rîs, earlier hris, n., ‘branch’; corresponding to Du. rijs, AS. hrîs, OIc. hrîs, m., ‘twig, branch’; Goth. *hreis, n., is wanting. The Teut. cognates (Zweig, ‘that which shakes, lives’) accord well with Goth. hrisjan, ‘to shake,’ OSax. hrissian, AS. hrissan, ‘to tremble, quake.’ —