the word "Balls" (implying testicles) Spelled Backwards. It seems to have varied usage.
In the way I learned it, Often followed by an argument between the two parties at hand. (See example)
Person A: Hey Guess what?
Person B: What?
Person A: Sllab! (NOTE: PERSON B MUST SAY "WHAT" IN ORDER FOR PERSON A TO RELPY "SLLAB")
This argument often follows for those "in the know":
Person B: Dickbag/Stickbag (depending on whether person B is in JHS Percussion or not)
Person A: Down your throat
Person B: Hope You choke
A variant has Person A replying to "what" with "Sllab Dickbag," creating a role reversal and ends wit person A winning the "Argument"
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