One exploiting others (4)
I believe the answer is:
user
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">one exploiting others</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 user that I've seen before include "Exploiter (of others)" , "Right long-established" , "Junkie's" , "Drug taker" , "One taking drugs" .)