#peen  the part of a hammerhead opposite the flat striking surface (may have various shapes)
  supertype:  part.physical_object__portion  something less than the whole of a human artifact: "the rear part of the house"; "glue the two parts together"
  part of:  hammerhead  the striking part of a hammer
     part of:  hammer  a hand tool with a heavy rigid head and a handle; used to deliver an impulsive force by striking

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