fornicate

i. [Eccles. Lat. fornicatus, pa. par. of fornicor, from Cla . Lat. fornix (gen it. fornicis )=(1) a vault, an arch, (2) a brothel.] To commit fornication; to be lewd; to have unlawful sexual intercourse. for-ni-cate, for-ni-cat-ed, a. [Lat. fornicatus =arched, vaulted; fornix (gen it. fornicis ) = an arch, a vault.] 1. Arch .: Vaulted like an oven or furnace; arched; concave within and convex without. 2. Bot .: Arching over, as a fornicate leaf.