Reflective surface (6)
I believe the answer is:
mirror
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">reflective surface</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 mirror that I've seen before include "Daily paper" , "parrot?" , "Looking-glass" , "Something studied constantly by the vain?" , "model" .)