#ventricle  one of four connected cavities in the brain; is continuous with the central canal of the spinal cord and contains cerebrospinal fluid
  supertype:  bodily_cavity__cavity__cavum  (anatomy) a natural hollow or sinus within the body
  part:  spinal_fluid
  part of:  encephalon
  subtype:  fourth_ventricle  an irregular ventricle between the third ventricle and the central canal of the spinal cord
  subtype:  third_ventricle  a narrow ventricle in the midplane below the corpus callosum; communicates with the fourth ventricle via the Sylvian aqueduct
  subtype:  lateral_ventricle__lateralventricle  either of two horseshoe-shaped ventricles one in each cerebral hemisphere; they communicate with the third ventricle via the foramen of Monro

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