#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"
  subtype:  cantle  ladder-back
  part of:  car_seat__carseat  a seat in a passenger car
     part of:  passenger_car__passengercar__coach__carriage  a railcar where passengers ride
  part of:  chair  a seat for one person, with a support for the back

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