15
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.
"Hey John come in here! I'm about to drop a Fat Man!"
by hankmaster69 November 08, 2017
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16
The local drug dealer of a small town know for being a whistle-blower and sporting a shockingly small penis.

He lives a meaningless life inside his bunker.
Hey I'm going to go find the fatman of this town and get wasted bro
by Wrong Monster November 20, 2020
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17
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.
by Anonymous April 19, 2003
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