Narcotic derived from poppies (5)
I believe the answer is:
opium
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">narcotic derived from poppies</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 opium that I've seen before include "De Quincey confessed to eating it" , "Addictive drug made from poppies" , "Dried juice of white poppy" , "The stuff of wars" , "Narcotic derived from poppy" .)