When you pack/stack the cone of your bong. You cannot use this word if you have a home made bong, it doesn't work like that.
Usually a fat bowl occurs when you get home from work or more commonly when you return from school, escape the girlfriend/parents.
Whats the time man?
2:45
Bitch-sticks I can't wait to get home and smoke a big fat bowl.
I hear that.

Where's Gemma
Gave the slip, she's doin' my fucking head in
Well I got a fat bowl for you homes!
Shit yeah!

Every night when George got home Martha would have a fat bowl waiting for him, soon as he walked in the door.
(inaccurate film reference from dazed and confused"

by dat-ting June 13, 2007
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Too Fat Bowl Syndrome (TFBS) is a condition that plagues stoners across the nation. TFBS occurs when one is packing a device used for smoking marijuana with marijuana and over packs or stuffs the bowl to the point that no suction occurs. Many have hypothesized the reason that TFBS occurs. The prevailing theory is that because marijuana makes you tired, therefore lazy, you lazily pack the bowl and pack it so tightly that it is sealed. Another theory is that marijuana users will pack bowls so large that they last many rotations, eliminating the need to move, also because of the laziness caused by marijuana. No one wants to keep packing bowls. These two theories coincide and are generally analogous to each other. However recently, a rogue theory has come about that some people just like fat bowls. While all the theories may have some truths to them, only one thing is certain about TFBS: it is an epidemic, and there is no solution. It will never stop.
Stoner 1: I've never seen a bowl this fat! You definitely have Too Fat Bowl Syndrome.
Stoner 2: DUDE, THIS BOWL IS TOO FAT! Your TFBS is acting up.
Stoner 3: Whats a nigga to do?
Stoner 4: What you need to do is puff puff pass bitch.
by Weed Smokers United January 10, 2008
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