Definition of "vulva"

The wedge-shaped character was the triangle, the archaic Paleolithic sign of the vulva; the pubic triangle was at the end of the phallic stylus.

1981, William Irwin Thompson, The Time Falling Bodies Take to Light: Mythology, Sexuality and the Origins of Culture, London: Rider/Hutchinson & Co., page 22

Many of the less-sophisticated works are sexual in nature. Among the most common images are stylised vulvas, whole flocks of which appear on some cave walls.

2018, Tim Flannery, Europe: A Natural History, page 216