"booyasha" means as much as gotcha, or "pinned you down". it's used to show someone you found a weak spot in their explanations or to support someone who found a flaw in someone's doing.
a: "This whole Chatrooms is filled with FREAKS and RETARDS!"
b: "You're here too."
b: "booyasha! ;)"
b: "You're here too."
b: "booyasha! ;)"
by thetruephoenix May 15, 2004