When you are about to tell a joke to an audience & someone pre-empts all or part of the joke & takes the credit for the laughter after the punch line
Mick: Did you hear the one about the incy wincy piano...
Andy: & the 12 inch pianist!
Crowd: hahahahahah
Andy: Thanks, funy joke hey!
Mick: Andy, your a joke jumper
by Down Town Steve Brown June 22, 2006
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