#hairline  the natural margin formed by hair on the head
  supertype:  #bounds__boundary  the line or plane indicating the limit or extent of something
  part:  #widow's_peak
  part of:  #hair  dense growth of hairs covering the body or parts of it (as on the human head); helps prevent heat loss; "he combed his hair"
     part of:  #integumentary_system__integumentarysystem  the skin and its appendages

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