Of the upper hipbone (5)
I believe the answer is:
iliac
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">of the upper hipbone</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for iliac that I've seen before include "Pertaining to hip bone" , "bottom of a hip bone" , "Like certain body parts" , "Relating to part of the hip bone" , "hipbone" .)