fissur

n. (Anat.) The act of dividing or opening; the state of being fissured. [ 1913 Webster ]

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. [ 1913 Webster ]

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. [ 1913 Webster ]

v. t. To cleave; to divide; to crack or fracture. [ 1913 Webster ]

‖n. [ NL., dim. of L. fissura a fissure. ] (Zool.) A genus of marine gastropod mollusks, having a conical or limpetlike shell, with an opening at the apex; -- called also keyhole limpet. [ 1913 Webster ]