1) Laughing so hard at a semi-comical joke that your anus begins to ache.

2) Releasing of severe flatulence to the point where your rectum starts bleeding.
1) "I laughed so hard at Tom's stupid joke that my booty hurts from gusting a butt."

2) "Man, that chili grande did my ass dirty. I think I need to go home and put some Neosporin on my bootyhole cause I just gusted a butt."
by Dr. Nooch March 10, 2012
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