Main Entry: fis·sure

Pronunciation: \ˈfish-ər, British also ˈfish-yu̇r\

Function: noun

1 : a natural cleft between body parts or in the substance of an organ: as a : any of several clefts separating the lobes of the liver b : any of various clefts between bones or parts of bones in the skull c : any of the deep clefts of the brain ; especially : one of those located at points of elevation in the walls of the ventricles—compare sulcus d : anterior median fissure ; also : posterior median septum
2 : a break or slit in tissue usually at the junction of skin and mucous membrane <fissure of the lip>
3 : a linear developmental imperfection in the enamel of a tooth

—fis·sured \ˈfish-ərd, British also ˈfish-yu̇rd\ adjective