Acetabulum - bowl

The hip joint is of the ball and socket variety. The head of the femur/thigh bone acts as the ball while the acetabulum, a deep ovoid hip bone depression acts as the socket by receiving the femoral head. The acetabulum is so named because it resembles a wide-mouthed vessel used in Greco-Roman times to store vinegar at the dining table from which diners would periodically dip their food – the acetabulum.

Reference:

Smith W (ed), 1870, Dictionary of Greek and Roman Antiquities, 2nd edition, 1870, Little Brown and Company, Boston, page 4. Go to reference
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 Acetabulum

 

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