#helm.steering_system  steering mechanism for a vessel; a mechanical device by which a vessel is steered
  supertype:  steering_system__steering_mechanism  a mechanism by which something is steered (especially a motor vehicle)
  subtype:  wheel.helm  a circular helm to control the rudder of a vessel
  part of:  motorboat__powerboat  a boat propelled by an internal-combustion engine
  part of:  sailing_vessel__sailingvessel__sailing_ship__sailingship  a vessel that is powered by the wind; often having several masts
  part of:  ship  a vessel that carries passengers or freight
  part of:  tugboat__tug__towboat__tower  a powerful small boat designed to pull or push larger ships

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