gambling game vs gaming

gambling game and gaming both are nouns.

Word	Noun	Adjective	Verb	Adverb
gambling game	Yes	No	No	No
gaming	Yes	No	No	No

As nouns, gaming is a hypernym of gambling game; that is, gaming is a word with a broader meaning than gambling game:

gambling game: a game that involves gambling
gaming: the act of playing for stakes in the hope of winning (including the payment of a price for a chance to win a prize)

Other hypernyms of gambling game include gambling, play, game.

gambling game (noun)	gaming (noun)
a game that involves gambling	the act of playing for stakes in the hope of winning (including the payment of a price for a chance to win a prize)