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An offensively large dump. A crap of such grave proportions, that should the cruel bastard decide to deliver it whole (without any effort of pinching it off, flushing in between), such a deed would amount to nothing less than an act of pure, unabated vandalism; a destruction of public or private property, with due compensation and mandatory letter of apology to the caretaker of said toilet.
Accomplice: Where ya goin?
Offender: Just poppin' into the loo to squeeze out a fat rat.
*closes door*
*speaking through the door, the conversation continues*
Accomplice: Have you prepared you're letter of apology?
Offender: Aye, writing it on the walls as we speak.

"The fuck?! Who broke my toilet? Whoever just laid this brick, fess up now, or when I find out, I swear I'll shove this fat rat back up your cursed cornhole so far, you'll be belching farts for the next week and a half!"
by TSVandenberg July 11, 2012
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A Guinea Pig... A vile little creature that resembles nothing so much as a rat, if that rat were designed by GM and built by AMC.
Mom: So... Would you like to get a pet?

Kid: Sure. Anything but a fat rat.

A: What -is- that smell?

B: Oh, that's my brother's fat-rats. He changes their litter about as often as he showers.
by Honor July 22, 2008
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Imagine your at the bottom of a darkwell.

Now open your eyes.
Wait why tf would you open your eys if you cant see shit.
Hello You FATRAT
by Incredible Thoughts December 17, 2018
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