#notochord  a flexible rodlike structure that forms the supporting axis of the body in the lowest chordates and lowest vertebrates and in embryos of higher vertebrates
  supertype:  spinal_column__vertebral_column__vertebralcolumn__spine__backbone__back__rachis  the series of vertebrae forming the axis of the skeleton and protecting the spinal cord; "the fall broke his back"
  subtype:  urochord  a notochord of a larval tunicate typically confined to the caudal region

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