1) The scent emanating from a morbidly obese person who has chronically poor hygiene. 2) A foul odor that lasts more then 30 minutes after a morbidly obese person has defecated.
"You know how I can tell he can't reach to wipe his butt? The fat fog you smell when he walks by".
by MR.ZERO July 23, 2011
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