#tuber  a fleshy underground stem or root serving for reproductive and food storage
  supertype:  stalk__stem  a slender or elongated structure that supports a plant or fungus or a plant part or plant organ
  subtype:  water_chestnut__waterchestnut  edible bulbous tuber of a Chinese marsh plant
  subtype:  potato_bean__groundnut__wild_bean  nutlike tuber; important food of Native Americans
  subtype:  Jerusalem_artichoke  edible tuber of the Jerusalem artichoke
  subtype:  yam.tuber  edible tuber of any of several yams
  subtype:  sweet_potato.tuber__sweetpotato  the fleshy root of the sweet potato vine

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