A fold of mucous membrane tissue that attaches the lips and cheeks to the alveolar mucosa (and/or gingiva) and underlying periosteum.
A fold of mucous membrane under the tongue or by the clitoris.
Also known as the fraenum or frenulum, this is a fold of tissue that prevents free movement of a body part. The lingual fraenum is a fold of mucous membrane that anchors the bottom of the tongue to the floor of the mouth. The penile fraenum connects the foreskin to the base of the glans penis.
A fold of mucous membrane that connects two parts, one more or less movable, and checks the movement of this part.
A crease of skin or mucous membrane that restricts the mobility of an organ.