cranioschisis

noun
cra·​ni·​os·​chi·​sis | \ ˌkrā-nē-ˈäs-kə-səs How to pronounce cranioschisis (audio) \
plural cranioschises\ -​ˌsēz How to pronounce cranioschises (audio) \

Medical Definition of cranioschisis

: a congenital fissure of the skull