A chronic, diffuse, unremitting sensation of burning of the vulva (the female external genital organs including the labia, clitoris, and entrance to the vagina); a painful sensation which may extend to the perineum, thigh, or buttock and is often associated with discomfort in the urethra and rectum: Sally learned from her gynaecologist that a case of essential vulvodynia has many causes, for example, from a vulva irritation, a vagina infection, or from herpes.