What part of the body is called ilium?

Ilium is the uppermost and largest part of the hip bone, also known as the innominate bone. It forms the superior and lateral portion of the hip bone and articulates with the sacrum posteriorly and with the pubis and ischium anteriorly. The ilium has a broad, fan-shaped structure and contributes to the formation of the acetabulum, the socket that receives the head of the femur. It has several anatomical features, including the iliac crest, anterior superior iliac spine, and anterior inferior iliac spine, which serve as attachment points for muscles and ligaments.