The foul -- yet sometimes pleasant -- odor that emits from the behind of a person who, usually, is unaware of the problem. Take note, though, that this is not akin to a fart, but rather the result of untamed butt-cheeks that contain the remnants of doody, old hairs, weasels and other objects that gain smelly-momemtum with age.
During intercourse: "Cindy, I'm sorry, but doing you from behind is simply unbearable due to your butt whiff"

During observational conversation: "Jim, did you just catch Mary's butt whiff as she walked by? Disgusting!"
by Hamilton P May 11, 2007
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