#black_walnut__blackwalnut  American walnut having a very hard and thick woody shell
  supertype:  walnut  nut of any of various walnut trees having a wrinkled two-lobed seed with a hard shell
  part of:  black_walnut_tree__black_walnut__blackwalnut__black_hickory__blackhickory__Juglans_nigra  North American walnut tree with hard dark wood and edible nut

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