Unoriginal reply (4)
I believe the answer is:
echo
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">unoriginal reply</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 echo that I've seen before include "What evokes memories" , "Greek nymph, spurned by Narcissus, who pined away until only her voice remained" , "Mimic" , "Be suggestive of" , "Send back" .)