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in architecture, the large vessel of a warm bath in the Roman thermae. These were cut out of great blocks of marble and granite, and have generally an overhanging lip. There is one in the Vatican of porphyry over 12 ft. in diameter.

In entomology, it is applied specifically to the upper lip of an insect, the lower lip being termed labium.

In anatomy:

The Glenoidal labrum is a lip-like projection of cartilage on the scapula.

The acetabular labrum is a ring of cartilage that surrounds the acetabulum (the socket of the hip joint).