Star among compulsive gamblers (4)
I believe the answer is:
vega
'star' is the definition.
(Vega is an example)
'among compulsive gamblers' is the wordplay.
'among' indicates the answer is hidden within the clue.
'VEGA' is hidden within 'compulsive gamblers'.
(Other definitions for vega that I've seen before include "First magnitude star" , "Gave turn to a star" , "Fifth brightest star" , "Bright star of constellation Lyra" , "Brightest star of constellation Lyra" .)