The Collaborative International Dictionary
Fissure \Fis"sure\, n. [L. fissura, fr. findere, fissum, to cleave, split; akin to E. bite: cf. F. fissure.] A narrow opening, made by the parting of any substance; a cleft; as, the fissure of a rock.
Cerebral fissures (Anat.), the furrows or clefts by which the surface of the cerebrum is divided; esp., the furrows first formed by the infolding of the whole wall of the cerebrum.
Fissure needle (Surg.), a spiral needle for catching
together the gaping lips of wounds.
--Knight.
Fissure of rolando (Anat.), the furrow separating the frontal from the parietal lobe in the cerebrum.
Fissure of Sylvius (Anat.), a deep cerebral fissure separating the frontal from the temporal lobe. See Illust. under Brain.
Fissure vein (Mining), a crack in the earth's surface
filled with mineral matter.
--Raymond.