An Etymological Dictionary of the German Language/Koppel

by Friedrich Kluge

Koppel, f. and n., ‘leash,’ from MidHG. koppel, kopel, kuppel, f. (m. and n.), ‘tie, connection,’ especially ‘leash,’ then collect. ‘pack of hounds,’ also ‘band’ generally; from Lat. copula, MidLat. also cupla (the latter also ‘couple of hounds in a leash’), whence also Fr. couple, E. couple, Du. koppel, ‘couple, multitude, troop.’