Kind of bone (6)
I believe the answer is:
tarsal
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">kind of bone</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that tarsal is a type of bone)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for tarsal that I've seen before include "To do with bones of upper foot" , "One of the seven ankle bones" , "Foot bone" , "Of the bones making up the foot" .)