Labrets

Labret
Nicknames	Mao
Location	Labrum (below bottom lip, above chin)
Healing	Ranging from 3 - 6 weeks

A labret is one form of body piercing. Taken literally, it is any type of adornment that is attached to the lip (labrum). However, the term usually refers to a piercing that is below the bottom lip, above the chin. It is sometimes referred to as a "tongue pillar" or a "soul patch piercing."

The traditional pronunciation of labret in anthropology is /ˈleɪbrᵻt/ LAY-brət. It derives from the Latin labrum "lip" and the diminutive suffix -et. However, many in the body-piercing industry give it the pseudo-French pronunciation /ləˈbreɪ/ lə-BRAY, though it is not a French word.

The labret was a traditional piercing among the American Northwest Coast Indians, where it was related to status:

"access to labrets. After 3,000 BP, a divergence in labret wear in north and south coasts. In the north from 1500 - 3500 BP, more labrets worn by males. After 1500 BP, labrets worn by females. In the south, between 2000 - 3500 BP, worn by males and females, but from 2000 BP on, labrets generally disappear and are replaced by cranial deformation by free males and females of whatever class (e.g. elite or commoner). So, for 4,000 years on the northwest coast, it was important to distinguish certain individuals in a very direct manner; either by cranial deformation or by labret wear. Gender and geographical region may also be identified by these methods."

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Wikipedia