An Etymological Dictionary of the German Language/Abt
Abt, m., ‘abbot,’ from the equiv. MidHG. apt, abbet, abbât, OHG. and MidHG. abbā̆t, m.; comp. Du. abt, AS. abbod (with an abnormal d), and less frequently abbot, E. abbot. Borrowed with a change of accent in OHG. from MidLat. abbât- (nom. sing. abbas), ‘abbot’; comp. Ital. abáte, Fr. abbé, OIr. abb, acc. abbaith. It will be seen under Kreuz that in words borrowed from Lat. the stem of the oblique cases as well as the nomin. often forms the base; with regard to the ecclesiastical terms borrowed in OHG. comp. among others Mönch, Nonne, Papst, Priester, Probst.