s]
.| lateral fissure. |

| the fissure separating the frontal, temporal, and parietal lobes of the cerebrum. |
fissure of Sylvius fissure of Syl·vi·us (sĭl'vē-əs) or sylvian fissure
n.
The deepest and most prominent of the cortical fissures of the brain, extending between frontal and temporal lobes, then back and slightly upward over the lateral aspect of the cerebral hemisphere. Also called lateral cerebral sulcus.