/ˈilēəm/
Noun, pl. ilia
1. The uppermost and the largest bone of the pelvis that is composed of two major parts in humans: the body and the ala. This bone articulates on the inner aspect with the sacrum. (biology-online.org)
2. A bone in the pelvis. (wikipedia.org)
3. The upper and widest of the three bones that make up each side of the hipbone and pelvis. (wiktionary.org)
4. The large broad bone forming the upper part of each half of the pelvis. (Google Dictionary)
Word origin: From Latin ilia (plural) “groin, flank”