An Etymological Dictionary of the German Language/Backbord
Backbord, n., ‘larboard,’ from LG. (comp. the preceding word); comp. Du. bakboord (AS. bœcbord), whence also the equiv. Fr. bâbord; lit. ‘the left side of the ship to the back of the helmsman, who is steering with his right hand, the left hinder-part of the ship.’ Du. and E. back is an OTeut. word, which was, however, very early obsolete in HG. (see the following word); OHG. bah, OSax. bak, AS. bœc, E. back, OIc. bak, n., ‘back,’ Goth. *bak, n. From LG. is also derived HG. Bord. See the latter.