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1 definition by StapleNibo

A Acronym derived on the MMORPG "Runescape" First used by a player known as Staple,or "Nibo." It means (M)ad (S)ad (B)ad as a flame toward raging players that are considered "Bad" at the game.
l0l why you so msb bro?!
by StapleNibo April 06, 2011