1 definition by Jbird, E to the B

a verbal cue of encouragement used by a bro to congratulate the level of hardness (masculinity) that another bro has.
Usually follows one or more of the following activities: popping a collar, getting crunk, making a tackle in football, using homosexually driven humor, riding a raised truck, taking advantage of a drunk girl at a party, as well as many more. Once the phrase has been exclaimed, it is immediately repeated by nearby bros as to show off their level of masculine camaraderie
Erik: Hey guys, Justin just tapped this bitch. (to Justin) Jeah Boi!!!
Crowd: Jeah Boi!
by Jbird, E to the B November 1, 2006
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