FIS'SURE, noun fish'ure. [Latin fissura, from findo, to split.] 1. A cleft; a narrow chasm made by the parting of any substance; a longitudinal opening; as the fissure of a rock. 2. In surgery, a crack or slit in a bone, either transversely or longitudinally, by means of external force. 3. In anatomy, a deep, narrow sulcus, or depression, dividing the anterior and middle lobes of the cerebrum on each side. FIS'SURE, verb transitive To cleave; to divide; to crack or fracture.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI