#upper_surface__uppersurface  the side that is uppermost
  supertype:  #object_side__side  an extended outer surface of an object; "he turned the box over to examine the bottom side"; "they painted all four sides of the house"
  subtype:  #ceiling  the overhead upper surface of a room; "he hated painting the ceiling"
     subtype:  #overhead  (nautical) the top surface of an enclosed space on a ship

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