1 definition by FireApocalypse :3

Laughing uncontrolably loud.
When your sitting in a quite area and you can tell someone in the other room told a really good joke because you can hear them laughing so hard they start pounding on the table.

Tom: "Hey man did you find the answer to numbe......"

People in other room: "ah ha ha ha no fuckin' way ha ha ha ha ha hAAAAA!!!"

Daniel: "Wow those fuckers are really yucking it up in there aren't they"

Tom: "Yeah someone must of told a real knee slapper in there." "Good enough to keep us from working."
by FireApocalypse :3 May 7, 2011
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