#fetlock  projection behind and above a horse's hoof
  supertype:  outgrowth__process__proces  a natural prolongation or projection from a part of an organism either animal or plant; "a bony process"
  part of:  horse's_foot__horse'sfoot__horse's_hoof__horse'shoof  the hoof of a horse
     part of:  horse__Equus_caballus  solid-hoofed herbivorous quadruped domesticated since prehistoric times

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