An Etymological Dictionary of the German Language/Annotated/Kuppeln

Kuppeln, verb, ‘to couple, fence (a field),’ from Middle High German kuppeln, koppeln, ‘to leash, bind, fetter, unite’; Middle High German kuppelspil, ‘coupling,’ kuppelœre, ‘match-maker, procurer,’ and kuppelœrinne, the feminine form; a derivative of Koppel, Latin copulare.