Nautical. a drain at the edge of a deck exposed to the weather, for allowing accumulated water to drain away into the sea or into the bilges. Compare freeing port.
2.
a drain, closed by one or two flaps, for allowing water from the sprinkler system of a factory or the like to run off a floor of the building to the exterior.
3.
any opening in the side of a building, as in a parapet, for draining off rain water.
"opening in a ship's side at deck level," late 15c., perhaps from O.Fr. escopir "to spit out," or related to Du. schop "shovel," or from M.E. scope "scoop" (see scoop).