Literally, ‘the cup' in Latin. The acetabulum is the ‘socket' of the ball and socket hip joint. It is made of the three bones of the pelvis and is covered with gliding cartilage called articular cartilage. The ball of the hip joint, the femoral head moves within the acetabulum.
The cup-shaped socket of the hip joint. In fact, in Latin an "acetabulum" is cup, a vinegar cup. The acetabulum is a feature of the pelvis. The head (upper end) of the femur (the thighbone) fits into the acetabulum and articulates with it, forming a ball-and-socket joint.
The cavity into which an appendage is articulated.