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A female asshole resembles a taco turned 90 degrees and colored brown. The opposite of a Pink Taco only referring to a females asshole.
She has a very nice brown taco, it was warm and tight.
by SickAsHell September 27, 2005
a very untidy vagina; when one does not clean their vagina
Guy 1: Dude I could not go down on her.

Guy 2: Why not?
Guy 1: She has a brown taco.
by Johnny Five-O September 14, 2011
When a man takes a shit in a chicks twatter.
did you see the long lost princess diana sex tape? the prince shits right in her roast beef... brown taco.
by Lifter5 January 05, 2008
Taking a turd, laying it in a woman's vulva, then eating it.
"Don't mind my breath, I've been eating brown taco!"
by D. Finer November 28, 2006