An Etymological Dictionary of the German Language/Annotated/Fach
Fach, neuter, ‘compartment, shelf, panel, special branch,’ from Middle High German vach, Old High German fah(hh), neuter, ‘part, division of space, of a partition, wall, &c.,’ also ‘contrivance, an enclosed space in water for catching fish, fish-weir, hurdles for fishing’; with the latter meanings some have connected Greek πάγη, ‘noose, snare, fishing hurdles,’ to which there is no objection phonetically. Yet we must proceed in the case of the High German word as well as of Anglo-Saxon fœc, ‘space, time,’ from a general and primary sense, such as ‘division, a portion of space or time.’ Allied to High German fügen. —