Make void (5)
I believe the answer is:
annul
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">make void</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for annul that I've seen before include "Cancel, make void" , "Repeal, rescind" , "Declare (a law) invalid" , "Quash" , "Render invalid" .)