#engine  motor that converts thermal energy to mechanical work
  supertype:  motor  machine that converts other forms of energy into mechanical energy and so imparts motion
  subtype:  aircraft_engine  automobile_engine  auxiliary_engine  generator  heat_engine  reaction-propulsion_engine
  part:  camshaft  has cams attached to it
  part:  gearing__gears__gear__geartrain__power_train__powertrain__train  wheelwork consisting of a connected set of rotating gears by which force is transmitted or motion or torque is changed; "the fool got his tie caught in the geartrain"

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