What is Fat Sac?
1.
a large sac of marijuana.
"Let me buy that fat sac off you."
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2.
A water filled bag used to add ballast to boats in order to produce a larger wake. This enables wakeboarders to get more air.
The Fat Sac ads up to 600 pounds of weight to your boat.
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3.
An exceptionally large scrotum.
DAMN!!!!! DAT fool's got a FAT SAC!!!!