Front's opposite (4)
I believe the answer is:
back
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">front's opposite</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for back that I've seen before include "defensive player" , "Stern" , "See 17" , "Returned" , "Support - defender - reverse" .)