The wet, splattered butt you are left with after a high velocity oatmeal type dump. This is often the result of eating a lot after a long drinking binge. Most often splatterbutt sessions are followed by a shower and a serious scrubbing except in the case of college freshman.
After the kegger the other night we went and killed a couple of jalpeno meat lover pizzas. I spent the whole morning with splatterbutt and had to shower four times.
A temporary condition suffered while defecating that follows a bad case of diarrhea; typically characterized by explosive flatulance accompanied by the release of particulated fecal matter and the remaining contents of one's intestinal lining.