Main Entry: il·i·um

Pronunciation: \ˈil-ē-əm\

Function: noun

Inflected Form(s): plural il·ia \-ē-ə\

: the dorsal, upper, and largest one of the three bones composing either lateral half of the pelvis that in humans is broad and expanded above and narrower below where it joins with the ischium and pubis to form part of the acetabulum

[ilium illustration]