Uterine fornix: The fornix of the uterus (known in medical Latin as the "fornix uteri") refers to the anterior (front) and posterior (back) recesses into which the upper vagina is divided. These vault like recesses are formed by protrusion of the cervix into the vagina. The fornix uteri is also known as the fornix vaginae (the vaginal fornix).
In anatomy, a vault like or arched structure. "Fornix" is the Latin word for "vault or arch." A fornix may be anywhere in the body.
The fornix in the brain is a fibrous, arching band connecting the two lobes of the cerebrum.
The fornix conjunctivae refers to loose, arching folds connecting the conjunctival membrane lining the inside of the eyelid with the conjunctival membrane covering the eyeball.
("Fornix" is closely related to "fornication." It seems that prostitutes in ancient Rome used to hang out under the arches of certain public buildings. The act of carrying on an illicit sexual relationship consequently came to be called "going under the arches," fornication.)