An Etymological Dictionary of the German Language/Boje

by Friedrich Kluge

Boje, f., ‘buoy,’ from the LG. boje, Du. boei, E. buoy, which are borrowed from Rom.; comp. Fr. bouée, ‘buoy,’ OFr. buie, ‘chain, fetter', whence MidHG. boie, ‘fetter'. The ultimate source of the word is Lat. boja, ‘fetter’; the buoy was originally a floating piece of wood with a rope fastened to it.