A Frenulum is a small piece of tissue that serves the function of restraining a mobile organ in the body - for example the tongue web. Frenula on the human body include several in the mouth, a few in the digestive tract, and some which are connected to both male and female genitalia.
Most frenula are found inside of the mouth: The frenulum linguae resides under the tongue, the frenulum labii superioris is inside the upper lip, the frenulum labii inferioris is inside the lower lip, and the buccal frena which connect the cheeks to the gum.
In a female, genital frenula include the frenulum clitoridis which is part of the clitoris hood, and the frenulum labiorum pudendi where the labia minora meet at the back.
In a male there is the frenulum preputii penis, which is an elastic band of tissue under the glans penis that connects to the prepuce, or foreskin to the vernal mucosa. Its function is to help pull the foreskin over the head of the penis.
All Frenulums are very delicate pieces of tissue and are very easily torn.