Indirect reference (8)
I believe the answer is:
allusion
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">indirect reference</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for allusion that I've seen before include "Subtle reference" , "A brief or indirect reference to something" , "Passing reference or indirect mention" .)