Bonce (4)
I believe the answer is:
head
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">bonce</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 head that I've seen before include "John on board" , "Chief; go first" , "Skull" , "Noggin" , "Person in charge" .)