A frenulum is a small fold of tissue that secures or restricts the motion of a mobile organ

Organ (anatomy)

In biology, an organ is a collection of tissues joined in structural unit to serve a common function. Usually there is a main tissue and sporadic tissues . The main tissue is the one that is unique for the specific organ. For example, main tissue in the heart is the myocardium, while sporadic are...

 in the body

Body

With regard to living things, a body is the physical body of an individual. "Body" often is used in connection with appearance, health issues and death...

.

In human anatomy

Frenula on the human body include several in the mouth

Mouth

The mouth is the first portion of the alimentary canal that receives food andsaliva. The oral mucosa is the mucous membrane epithelium lining the inside of the mouth....

, some in the digestive tract, and some connected to the external genitalia

Sex organ

A sex organ, or primary sexual characteristic, as narrowly defined, is any of the anatomical parts of the body which are involved in sexual reproduction and constitute the reproductive system in a complex organism; flowers are the reproductive organs of flowering plants, cones are the reproductive...

.

• Oral tissue: Frenula of the mouth
  Mouth
  The mouth is the first portion of the alimentary canal that receives food andsaliva. The oral mucosa is the mucous membrane epithelium lining the inside of the mouth....
  
   include the frenulum linguae
  Frenulum linguae
  The frenulum of tongue is the frenulum of the tongue, a small fold of mucous membrane extending from the floor of the mouth to the midline of the underside of the tongue.-Development:The tongue starts to develop at about 4 weeks...
  
  under the tongue
  Tongue
  The tongue is a muscular hydrostat on the floors of the mouths of most vertebrates which manipulates food for mastication. It is the primary organ of taste , as much of the upper surface of the tongue is covered in papillae and taste buds. It is sensitive and kept moist by saliva, and is richly...
  
  , the frenulum labii superioris inside the upper lip, the frenulum labii inferioris inside the lower lip, and the buccal frena which connect the cheeks to the gum. These can easily be torn by violent blows to the face or mouth, thus a torn frenulum is sometimes a warning sign of physical abuse
  Physical abuse
  Physical abuse is abuse involving contact intended to cause feelings of intimidation, injury, or other physical suffering or bodily harm.-Forms of physical abuse:*Striking*Punching*Belting*Pushing, pulling*Slapping*Whipping*Striking with an object...
  
  .

• Vulvular tissue: In females, genital frenula include the frenulum clitoridis
  Frenulum clitoridis
  The Frenulum clitoridis is a frenulum on the under-surface of the clitoral glans, created by the two medial parts of the labia minora.-External links:...
  
  of the clitoris
  Clitoris
  The clitoris is a sexual organ that is present only in female mammals. In humans, the visible button-like portion is located near the anterior junction of the labia minora, above the opening of the urethra and vagina. Unlike the penis, which is homologous to the clitoris, the clitoris does not...
  
   and the frenulum labiorum pudendi
  Frenulum labiorum pudendi
  In female human anatomy, the frenulum labiorum pudendi is a frenulum where the labia minora meet posteriorly.-Pathology:...
  
  (aka fourchette) where the labia minora
  Labia minora
  The labia minora , also known as the inner labia, inner lips, or nymphae, are two flaps of skin on either side of the human vaginal opening, situated between the labia majora...
  
   meet at the back.
• Penile tissue: The word frenulum on its own is often used for the frenulum of prepuce of penis
  Frenulum of prepuce of penis
  The word frenulum on its own is often used for the frenulum of prepuce of penis, which is an elastic band of tissue under the glans penis that connects to the prepuce, or foreskin to the vernal mucosa, and helps contract the prepuce over the glans. This is sometimes colloquially known as the "banjo...
  
   or frenulum preputii penis, which is an elastic band of tissue under the glans penis
  Glans penis
  The glans penis is the sensitive bulbous structure at the distal end of the penis. The glans penis is anatomically homologous to the clitoral glans of the female...
  
   that connects to the prepuce
  Foreskin
  In male human anatomy, the foreskin is a generally retractable double-layered fold of skin and mucous membrane that covers the glans penis and protects the urinary meatus when the penis is not erect...
  
  , or foreskin
  Foreskin
  In male human anatomy, the foreskin is a generally retractable double-layered fold of skin and mucous membrane that covers the glans penis and protects the urinary meatus when the penis is not erect...
  
   to the vernal mucosa, and helps contract the prepuce over the glans.
• Brain: Frenulum veli
  Frenulum veli
  The frenulum veli, or frenulum of superior medullary velum, also known as the frenulum veli medullaris superioris, cerebellar frenulum, or frenulum cerebelli is a slightly raised white band passing from the inferior end of the medial longitudinal fissure, through the groove between the...
  
  

An overly short oral or genital frenulum may require a frenulectomy or frenuloplasty

Frenuloplasty

A Frenuloplasty of tongue is a Frenuloplasty of the frenulum of tongue.A tight frenulum in this context is sometimes referred to as "tongue-tie" which is also known as ankyloglossia. In this condition the frenulum of the tongue restricts range of motion which may interfere with breastfeeding or...

 to achieve normal mobility.

In entomology

The word frenulum also refers to a bristle present at the root of the hindwing of most moth

Moth

A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...

s which engages with a small hook on the forewing (the retinaculum) to join the wings together.