The bony cup of the pelvis which receives the head of the femur.

An acetabulum was a small saucer or cup used to serve vinegar on dining tables. This was likened to the major concavity of the ilium bone that articulates with the head of the femur. 

Disclaimer: The definition of abducens nerve (see hyperlink for attribution and more information) has been modified such that its respective etymology and other related context has been integrated for educational purposes and without compromising the reasonable integrity of the definition. Please see Terms of Service for more details.