One of the most versatile phrases known. Fat poo can be used as an insult, an exclamation of a general displeasure, an exclamation of a general joy, a compliment (similar to saying "you're the shit"), or it could even be used on its own, but only in certain circumstances. These certain circumstances are usually if you are at a friend's house and there is no conversation, you could say fat poo to break the silence. Or perhaps you could say fat poo when you don't really have a response to something.
(insult)
Person 1: Dude you're stupid
Person 2: Yeah? Well you're a fat poo.

(General displeasure)
AW WHAT THE FAT POO, THAT WAS BULLSHIT!

(general joy)
AWWWW YEAH, FAT POO, THAT THING FINALLY CAME IN! I'M GENERALLY JOYOUS!

(Compliment)
Person 1: Dude you're really cool
Person 2: You're awesome
Person 1: You're amazing
Person 2: You're the fat poo

Person 1: R-really? That's so nice of you!

(On its own)
*4 friends are in a room*
*After 45 minutes of talking and laughing together, the room gets deafeningly silent*
*It is, indeed, awkward*
Person 1: ... Fat poo
Person 2, 3, and 4: lmao
by Nicky Big Dick September 11, 2016
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N: GepperRankins; To be a poo-poo head.
GepperRankins insinuated that I was a Ziggy "fanboy", so I called him a big fat poo-poo head.
by Skizo May 9, 2005
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An overweight person with their head resembling faeces (FAT poo head) or a person with their head resembling a large piece of faeces (FAT POO head)
Why did you throw my ball over the fence! I hate you, you FAT POO HEAD I HATE YOU
by yers police May 20, 2021
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a fat poo is a black man before he shits him self
asshole you do a fat poo
by titty honker October 19, 2020
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