Use a cigarette (5)
I believe the answer is:
smoke
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">use a cigarette</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 smoke that I've seen before include "'There's no . . . . . without fire'" , "Use a cigarette" , "Use tobacco" , "Cure (meat) over fire" , "Cure (food) - endanger health!" .)