This means leaving a very generous tip (usually 50-100%) when out drinking and/or dining. Especially when out with a large group of friends.
I'm going to FAT-TIP the bartender so that we will be remembered and taken care of for the rest of the night.
by Pmdmnym July 13, 2015
When a male has an abnormally large penis tip.
Ian has an extremely fat tip.
by Jimmy Lardbutt March 06, 2014