#backrest__back  a support that you can lean against while sitting; "the back of the dental chair was adjustable"
  supertype:  support.device  any device that bears the weight of another thing; "there was no place to attach supports for a shelf"
  part of:  car_seat  chair
  subtype:  cantle  the back of a saddle seat
  subtype:  ladder-back  a chair backrest consisting of 2 uprights with connecting slats

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