#underside__bottom__undersurface  the lower side of anything
  supertype:  #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:  #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"

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