#stair__step  support consisting of a place to rest the foot while ascending or descending a stairway; "he paused on the bottom step"
  supertype:  support.device  any device that bears the weight of another thing; "there was no place to attach supports for a shelf"
  subtype:  corbel_step  (architecture) a step or step-like projection on the top of a gable wall
  part:  riser  tread
  part of:  stairway__staircase__stairs__steps__step  a way of access consisting of a set of steps
     part of:  edifice__building  a structure that has a roof and walls and stands more or less permanently in one place; "there was a three-story building on the corner"; "it was an imposing edifice"

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