Spliff (6)
I believe the answer is:
reefer
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">spliff</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 reefer that I've seen before include "courses may be reduced by one" , "close-fitting garment" , "packed with cannabis?" , "Jack < 's joint" , "J" .)