When you have one hand masturbating and the other with a thumb in your butt (when you have diarrhea, as to stimulate it) and you are trying to time it right to where you shit yourself and cum at the same time.
Guy 1: Remember that one time at Ted Grogers house party when i had diarrhea.

Guy 2: Yea what about it?

Guy 1: i was neating off in his bathroom; there was shit and cum everywhere!

Guy 2: sweet!!! i neated off on my girlfriend two nights ago.

Guy 1: not cool dude, not cool.
by hutch n' sand October 11, 2009
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