Joint, acetabular
The hip joint by another name.
The acetabulum is the cup-shaped socket of the hip joint.
It is a key feature of the pelvic anatomy.
The head (upper end) of the femur (the thighbone) fits right into the acetabulum, articulates with it, and thereby forms a ball-and-socket joint, the largest in the human body.</P> The term 'acetabulum' is appropriate because in Latin it is a cup, a vinegar cup.