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An undesirable and unhygenic cocktail of sweat, piss and fanny lube from the fanny of a fat bird. Often pungent, rarley lethal.
"I sat on L-A-S's chair the other day and when I stood up, the backs of my trousers were wet with, what I believe to be, fanny diesel."
by felchmeister general October 29, 2003
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