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Also known as Poo Jabs.

Bum Shock is caused by a confusion at the Sphincter and is recognised by a short attack of pain in the anus. It is ultimately caused by needing a massive poo which hasn't quite brewed.

Ouch, my bum hurts.

You've got Bum shock!

by Gallimerde March 02, 2007
bum shocks are anal wind as told by 3 year old son
Oops! Bum shocks (then chuckles)
by Margi Sloan September 11, 2007