Betting game (4)
I believe the answer is:
faro
'betting game' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for faro that I've seen before include "City in Portugal's Algarve" , "Atlantic port" , "Card game - Portuguese resort" , "Card game - Algarve port" , "Gambling game - Algarve capital" .)