#sulcus  (anatomy) any of the narrow grooves in an organ or tissue especially those that mark the convolutions on the surface of the brain
  supertype:  #fissure  (anatomy) a long narrow slit or groove that divides an organ into lobes
  subtype:  #fissure_of_Rolando__Rolando's_fissure__central_sulcus__sulcus_centralis  a fissure extending upward on the lateral surface of both hemispheres; separates the frontal and parietal lobes
  subtype:  #fissure_of_Sylvius__Sylvian_fissure__lateral_cerebral_sulcus__sulcus_lateralis_cerebri  the deepest and most prominent of the cortical fissures; separates the frontal and temporal lobes in both hemispheres

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