#hub  the central part of a car wheel (or fan or propeller etc) through which the shaft or axle passes
  supertype:  #part.physical_object__portion  something less than the whole of a human artifact: "the rear part of the house"; "glue the two parts together"
  part of:  #car_wheel__carwheel  a wheel that has a tire and rim and hubcap; used to propel the car
     part of:  #motor_vehicle__motorvehicle__automotive_vehicle  a self-propelled wheeled vehicle that does not run on rails
  part of:  #electric_fan__blower  a fan run by an electric motor
  part of:  #propeller__propellor  a mechanical device that rotates to push against air or water

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