An Etymological Dictionary of the German Language/schmähen
schmähen, vb., ‘to abuse, revile, rail,’ from MidHG. smœhen, ‘to treat contemptuously,’ OHG. smâhen, vb., ‘to make small, lessen,’ see Schmach. Allied to ModHG. schmählich, adj., ‘abusive,’ MidHG. smœhelich, OHG. smâlîch, adj., which are identical with the OHG. adj. smâhi, MidHG. smœhe, adduced under Schmach.