#bitthead  the upper end of a bitt
  supertype:  end  either extremity of something that has length: "the end of the pier"; "she knotted the end of the thread"; "they rode to the end of the line"
  part of:  bollard__bitt  a strong post (as on a wharf or quay or ship for attaching mooring lines); "the road was closed to vehicular traffic with bollards"
     part of:  wharf__pier__wharfage__dock  a platform built out from the shore into the water and supported by piles; provides access to ships and boats

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