#sacrum  wedge-shaped bone consisting of five fused vertebrae forming the posterior part of the pelvis; its base connects with the lowest lumbar vertebra and its tip with the coccyx
  supertype:  bone__os  rigid connective tissue that makes up the skeleton of vertebrates
  part:  sacral_vertebra
  part of:  pelvis__pelvic_girdle__pelvic_arch__hip  the structure of the vertebrate skeleton supporting the lower limbs in humans and the hind limbs or corresponding parts in other vertebrates
     part of:  appendicular_skeleton  the part of the skeleton that includes the pectoral girdle and the pelvic girdle and the upper and lower limbs
        part of:  endoskeleton  the internal skeleton; bony and cartilaginous structure (especially of vertebrates)

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