1. A term for a woman's vagina, when receiving cunnilingus, has a sharp, sour, foul taste reminiscent to that of the condiment mustard.

2. A term for a woman's vagina that gives off such a foul odor so strong that it could result in casualties, much like Mustard Gas.
"Damn, girl. You need to do something about that mustard biscuit you got between your legs."
by JEII May 11, 2006
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