Fifty per cent (4)
I believe the answer is:
half
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">fifty per cent</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 half that I've seen before include "Wife the better one (joc.)" , "Fifty percent" , "Moiety" , "0.5" , "Some football" .)