The term 'Hipbone Parts' refers to the two bones that make up the pelvis, the ilium and the ischium. The ilium is the uppermost and largest of the two bones, and it forms the sides and the base of the hipbone. The ischium is the lowermost and smallest of the two bones, and it forms the back of the hipbone. Together, these two bones form the hipbone, which is an important part of the human skeleton.