Drawing upon (5)
I believe the answer is:
using
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">drawing upon</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for using that I've seen before include "addiction" , "Utilising" , "practice" , "Putting to a particular purpose" , "Exploiting for one's own advantage" .)