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An acronym for "Fat sack of shit", commonly used to insult people over the internet for being fat in real life.
Stfu you fsos go loose some weight.
by Jack stern June 11, 2008
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An acronym for "Fat sack of shit", commonly used to insult people over the internet for being fat in real life.
Stfu you fsos go loose some weight.
by Bob welling June 13, 2008
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eg. an individual who has reached the bottom of a curve, at a minus platform, giving him/her no options other then selling out.
F.S.O.

by ~GTS~ August 10, 2008
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An acronym for "Fat sack of shit", commonly used to insult people over the internet for being fat in real life.
Stfu you fsos go loose some weight.
by Jack stern June 11, 2008
Get the mug
Get a fsos mug for your guy Yasemin.