Vaginal introitus: The vaginal opening is called the introitus of the vagina. The Latin word "introitus" comes from "intro", into, within + "ire", to go = to go into. In anatomy, an introitus is thus an entrance, one that goes into a canal or hollow organ such as the vagina.
The vagina is a muscular canal extending from the cervix to the outside of the body. The word "vagina" is a Latin word meaning "a sheath or scabbard", a scabbard into which one might slide and sheath a sword. The "sword" in the case of the anatomic vagina was the penis. Love and war, it would seem, have been connected in the minds of people for millennia.