The proper name of any kind of food that will make one's butt fat.
Fat-Butt in a pan (Brownies), Fat-Butt in a bag (Chips), Fat-Butt in a Bucket (KFC) Fat-Butt in a flat box (Pizza), and Fat-Ass-In-A-Glass (Margarita) etc.

"Pass me another slice of that Fat-Butt. Wow, this is the best Fat-Butt I've had in a long time! No one makes Fat-Butt better than your Mom!"

by Patricia English September 26, 2007
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Two butt fat is when you are so fat it looks like you have two butts.
Keven, did you see that person he was so fat he had two butts.

Austin, pukes, i just lost my lunch yeah that is called two butt fat Keven.
by apple seller December 11, 2010
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