Use a cigarette (5)
I believe the answer is:
smoke
'use a cigarette' is the definition.
(I've seen this before)
This is all the clue.
(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!" .)