Mooch, as a cigarette (3)
I believe the answer is:
bum
'mooch as a cigarette' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for bum that I've seen before include "False" , "American hobo or English bottom" , "Layabout" , "American hobo or vulgar bottom" , "Begging" .)