labrum
UK[ˈleɪbrəm]US[ˈleɪbrəm]
n
A rim or edge of a part of the body, especially the socket of the hip joint or shoulder joint.
n
The upper lip in an insect or crustacean.
Etymology
The word 'labrum' is a direct borrowing from Latin, where it meant "lip" or "edge." In Latin, it was related to the verb lambere, meaning "to lick," and the noun labium, meaning "lip," sharing a common Proto-Indo-European root leb- or lab-, which carried the sense of "to lick" or "lip." This ancient connection to the concept of a lip or rim logically extended into anatomical terminology. In modern scientific English, it retains this core sense of a border or rim, specifically applied to describe the cartilaginous lip of a body socket in vertebrates or the upper mouthpart in arthropods.
Analysis
The word is a simplex loanword from Latin. It does not contain separable, meaningful morphemes within its modern English spelling.
Examples
The surgeon repaired the torn labrum in the athlete's shoulder.
In entomology, the labrum is part of the insect's mouth structure.
A tear in the acetabular labrum can cause hip pain and stiffness.