"A frenulum (or frenum) is a small fold of tissue that prevents an organ in the body from moving too far. There are frenula at several points of the body, including several in the mouth (frenulum linguae, f. labii superioris, f. labii inferioris of the tongue, upper and lower lips respectively), some in the digestive tract, and some connected to the external genitalia. In the female these include the frenulum clitoridis of the clitoris and the frenulum labiorum pudendi (aka. fourchette) where the labia minora meet at the back.
The word frenulum on its own is often used for the frenulum preputii penis, which is an elastic band of tissue under the glans penis that connects to the prepuce and helps contract the prepuce over the glans. It is often partially or totally removed during circumcision. When short or tight it may prevent normal retraction and inhibit normal sexual activity."