Applicable to males only. When you stroke your penis after you finish urinating to get all urine out. Usually only done by those with a masturbation addiction.
Tom: After I finished peeing, I started pissbating but I ended up masturbating and blew a load in my toilet.
Bill: Yeah dude I was there.
Means the same thing as inappropriate whizzination; When a pet dog or cat urinates in an inappropriate location, such as in a clothesbasket or onto a stack of important papers.
Nikki pissed onto some very important documents this morning; it's clear that she had inappropriate pissination.