Main Entry: cra·ni·os·chi·sis Pronunciation: "krA-nE-'äs-k&-s&s Function: noun Inflected Form: pluralcra·ni·os·chi·ses/-"sEz/ : a congenital fissure of the skull
cranioschisis cra·ni·os·chi·sis (krā'nē-ŏs'kĭ-sĭs) n. Congenital failure of the skull to close, usually accompanied by defective development of the brain.