My personal definition of gambling: Gambling is one of the ways of testing fortune with entertainment.

Personally I take gambling as entertainment and use it passing for free times. I never think that gamble will be one of my income sources or I will be dependent on gambling. I think it is only for doing fun and everybody should think like this IMO.
I don't know what is the correct definition of gambling. But I think this line is a better word for it.
From Dictionary:
* it is the activity or practice of playing at a game of chance for money or other stakes.