a euphemism for defecation, used in conjunction with 'little-boy' (i.e. urination). Commonly used as a noun, but acceptable in verb form.
I shouldn't have had that seventh enchilada. I've never had to take a fat-man so bad in my life.
I always fat-man before i go to work in the morning.
I always fat-man before i go to work in the morning.
by Anonymous April 19, 2003
Get the fat-manmug. Any adjective(s) or adverb(s) that describes how big something is; cannot be used by a fat guy without him looking fat.
Fat Guy: "Yeah, I'm a heavy advocate for lettuce".
Skinny Guy: "Haha, you sure are a heavy advocate".
Fat Guy: "Fat Man's Paradox".
Skinny Guy: "Haha, you sure are a heavy advocate".
Fat Guy: "Fat Man's Paradox".
by EmperorPomni October 27, 2024
Get the Fat Man's Paradoxmug. Stemming from the name of the nuclear bomb dropped on the Japanese city of Nagasaki; this term means to stand a top the tank of ones toilet and proceed to shit into the bowl from that height, resulting in a large splash, and if one has had Indian food, a considerable mess.
by hankmaster69 November 9, 2017
Get the Fat Manmug. A phrase sometimes used by one gay couple to describe another gay couple, where one of the two men given this moniker is tall and stout, while the other is short and thin. It is generally only uttered behind the couple’s back, but almost always with affection and not malice. The short thin man is actually “Fat Boy” (this is the twist).
As I explained to you last week, there will be four other couples staying at the beach house. You’ve met all of them except for Alan and Mark. They’re a fat man and little boy, both went to college, both are in their 40’s. What else do you want to know?
by TheRealPapaBob March 8, 2024
Get the Fat Man and Little Boymug. 
by Lex Patrone March 1, 2024
Get the Fat Manmug. On October 22nd, you are legally obliged to snog fat men if you see them, no permission needed. Particularly ones with beards.
by Teepy D October 21, 2022
Get the National Snog a Fat Man Daymug.