Adolescent with some cigarette ends (4)
I believe the answer is:
teen
'adolescent' is the definition.
(teenager)
'with some cigarette ends' is the wordplay.
'with' says the answer is hidden in the clue.
'TEEN' is hidden in the letters of 'some cigarette ends'.
(Other definitions for teen that I've seen before include "Young person" , "Adolescent, then adult-to-be" , "Youth" , "Adolescent (informal)" , "Youngster of a certain age" .)