#rudderpost__rudderstock  a vertical post at the forward edge of a rudder that enables the rudder to pivot
  supertype:  post.upright  upright consisting of a piece of timber or metal fixed firmly in an upright position
  part of:  rudder.steering_system  (nautical) steering mechanism consisting of a hinged vertical plate mounted at the stern of a vessel
     part of:  vessel.craft__watercraft  a craft designed for water transportation

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