When a group of males go accompany each other to take shits at the same time. This usually occupies all of the stalls in a public bathroom, and occasionally spreads to urinals and, in the extreme, sinks.
Bro 1: Yo man i have to take a dump.

Bro 2: Dude, me too!

Bro 3: Me three!

Bro 1: Yo lets go pull a dump session in the school bathroom!
by Agatster February 15, 2009
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