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A large shit that involves sweating and strainging so much that a change in wardrobe is necessary. Counting down from 10, start removing all your clothes. When all clothes are removed, release the load of shit from your anus and yell "Grand Slam". Then, if you are Spencer Meyer, continue to masturbate on the spot.
Dude, I just took a grand slam dump. It was awesome. Thats the second one this month!
by Jizzman69 January 20, 2008
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