#acorn  fruit of the oak tree: a smooth thin-walled nut in a woody cup-shaped base
  supertype:  fruit  the ripened reproductive body of a seed plant
  part:  acorn_cup
  part of:  oak_tree__oaktree__oak  a deciduous tree of the genus Quercus; has acorns and lobed leaves; "great oaks grow from little acorns"

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