Introitus, vaginal
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.
Medical dictionary.
2011.