#surface.bounds  the extended two-dimensional outer boundary of a three-dimensional object; "they skimmed over the surface of the water"; "a brush small enough to clean every dental surface"; "the sun has no distinct surface"
  supertype:  bounds__boundary  the line or plane indicating the limit or extent of something
  subtype:  interface  (physical chemistry) a surface forming a common boundary between two things (two objects or liquids or chemical phases)
     subtype:  oil-water_interface__oilwaterinterface  an interface forming the boundary between the non-miscible liquids oil and water
  subtype:  hard_palate  the bony part of the roof of the mouth
  subtype:  palate__roof_of_the_mouth  the upper surface of the mouth that separates the oral and nasal cavities
  subtype:  side.surface__face  a surface forming part of the outside of an object; "he examined all sides of the crystal"; "dew dripped from the face of the leaf"
     subtype:  beam-ends  (nautical) at the ends of the transverse deck beams of a vessel; "on her beam-ends" means heeled over on the side so that the deck is almost vertical
     subtype:  underside__bottom__undersurface  the lower side of anything
        subtype:  base.underside  a flat bottom on which something is intended to sit; "a tub should sit on its own base"
        subtype:  bilge  where the sides of the vessel curve in to form the bottom
           subtype:  bilges  in a vessel with two hulls, an enclosed area between the frames at each side
        subtype:  heel  the bottom of a shoe or boot; the back part of a shoe or boot that touches the ground
           subtype:  Cuban_heel  a broad heel of medium height on women's shoes
           subtype:  French_heel  a fairly high narrow heel on women's shoes
           subtype:  spike_heel__spikeheel__stiletto_heel  a very high narrow heel on women's shoes
           subtype:  stacked_heel__stackedheel  a heel made of many layers of leather
           subtype:  wedge_heel__wedgeheel__wedge  a heel that is an extension of the sole of the shoe
           subtype:  wineglass_heel__wineglassheel  a heel on a woman's shoe in the shape of a wineglass
        subtype:  sole  the underside of footwear or a golfclub
           subtype:  half_sole  shoe sole extending from the shank to the toe
           subtype:  insole__innersole  the inner sole of a shoe or boot
           subtype:  outsole  the outer sole of a shoe or boot
        subtype:  underbelly.underside  lower side: "the underbellies of clouds"
     subtype:  front_end__frontend__front__forepart  the side that is forward or prominent
        subtype:  forefront__head  the part in the front or nearest the viewer; "he was in the forefront"; "he was at the head of the column"
     subtype:  lee_side__leeside__lee  the side of something that is sheltered from the wind
     subtype:  backside__rear__back_end  the side of an object that is opposite its front; "his room was toward the rear of the hotel"
        subtype:  nape__scruff__nucha  the back side of the neck
        subtype:  rearward  direction toward the rear; "his outfit marched to the rearward of the tank divisions"
     subtype:  top_side__topside__upper_side__upperside__upside  the highest or uppermost side of anything; "put your books on top of the desk"; "only the top side of the box was painted"
        subtype:  crown.top_side__crest  the center of a cambered road
        subtype:  poll.top_side  the part of the head between the ears
        subtype:  pate.top_side__poll__crown  the top of the head
           subtype:  tonsure.pate  the shaved crown of a monk's or priest's head
        subtype:  desktop  the top of a desk
        subtype:  rooftop  the top of a (usually flat) roof
  subtype:  celestial_sphere__celestialsphere__sphere__empyrean__firmament__heaven__vault_of_heaven__welkin  the apparent surface of the imaginary sphere on which celestial bodies appear to be projected
  subtype:  end.surface  the surface at either extremity of a three-dimensional object: "one end of the box was marked `This side up'"
  subtype:  interior__inside  the inner or enclosed surface of something
  subtype:  exterior__outside  the outer side or surface of something
  subtype:  wavefront__wave_front  (physics) an imaginary surface joining all points in space that are reached at the same instant by a wave propagating through a medium
  subtype:  photosphere  the intensely luminous surface of the sun

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