A bet exclusively for boys. The simple terms are that the winner gets to hit the loser in the balls. Very high stakes bet which few dare to take.
Example 1:

Jon: What happened to Max? Why is he on the floor?
Mitch: Oh he just lost a balls bet with me

Example 2:

Austin: Balls bet that I can beat this level.
Ben: Deal.
Austin: *beats level*
Ben: Shit. Wait-not too hard-aaawwwww!
by Elsis May 18, 2016
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