F / fornĭcātĭo
noun

fornĭcātĭo

gen. fornĭcātōnis · gender feminine · decl. 3rd
a vaulting; arching over; a vault
a vaulting or arching over, a vault, arch (post-Aug.): parietum, Vitr. 6, 11: lapidum, Sen. Ep. 95, 53.