#fin_keel__finkeel  a metal plate projecting from the keel of a shallow vessel to give it greater lateral stability
  supertype:  plate  a sheet of metal or wood or glass or plastic
  subtype:  centerboard  a retractable fin keel used on sailboats to prevent drifting to leeward
  part of:  keel  one of the main longitudinal beams (or plates) of the hull of a vessel; can extend vertically into the water to provide lateral stability
     part of:  hull  the frame or body of ship
        part of:  vessel.craft__watercraft  a craft designed for water transportation

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