1)Irritation to the ass cheeks and hole due to wiping so much from an extended and violent bout of diarrhea.

2)The everlasting burning sensation one feels due to shitting after eating extremely spicy foods.
1) After having the squirts this morning I've got the worst lava rash. I must have used an entire roll of toilet paper!

2) Man, Ben is going to have lava rash for days after eating all that spicy indian food!
by yoderdude June 25, 2008
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