DEFINITION
The vulva is the external female genitalia, often inaccurately called the vagina, which is a passage or sleeve within the female mammal.
The vulva includes the mons pubis, labia majora and minora, clitoris, vaginal vestibule, perineal body, and their supporting subcutaneous tissues.
http://www.medscape.com/viewarticle/4084…
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FUNCTION
The vulvar structures cover the deeper structures of the female perineum (groin area). The labia maintain, by their apposition, the closure of the vaginal introitus (opening). The integument (skin) of the vulva has specialized nerve endings sensitive to touch. Mucus produced by the vestibular glands maintains the epithelial moisture in this region.
Its appearance also serves as a potent sexual stimulant.
From http://lucy.stanford.edu/vulva3.html:
