Hidden by (6)
I believe the answer is:
behind
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">hidden by</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 behind that I've seen before include "Hidden by; bottom" , "Seat" , "Serving time" , "Running late" , "Not in front" .)