When you sit down on the can expecting to unload a large deuce but air farts are the only thing that comes out...similar to the phrase shooting blanks.
John: "Hey Dave, where are you?"
Dave: "On the can, about to take a huge slam!"
Dave's Butt: "phhhhht"
John: "Ha! You're just pootin' blanks!"
by fpa_2010 August 12, 2010
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