the great myth ever known.....

The myth of the vagina dentata, or vagina with teeth, derives from primitive masculine dreads of the "mysteries" of women and sexual union. It evokes castration anxiety, whereby the man fears loss of the penis during intercourse, and more generally it relates to fears of weakness, impotence, or annihilation by incorporation (connected to unconscious notions of "returning to the womb").
-- Stories of the vagina dentata persist in aboriginal myths and legends (Egyptian, Indo-European, Greek, Native American, African), as well as in contemporary narratives, such as vulgar sexist jokes.
-- Sublimated expressions of this dread underlie stories of post-coital loss of strength, such as the biblical story of Samson and Delilah, or the deep social resonance of the recent (1993) Lorena and John Wayne Bobbitt incident in America.
-- Many narratives of "hero vs. monster" also rely on the myth: for instance, Oedipus and the Sphinx, whose mythic structure underlies Benchley's novel, Jaws.
-- Some cultural surgical practices, such as clitoridectomies and other female genital mutilations (including modern episiotomies), also relate to the myth. These practices physically inscribe an assertion of masculine domination that implies a dread of feminine powers.

From a contemporary, feminist, psychoanalytic perspective, Elizabeth Grosz writes:
"The fantasy of the vagina dentata, of the non-human status of woman as android, vampire or animal, the identification of female sexuality as voracious, insatiable, enigmatic, invisible and unknowable, cold, calculating, instrumental, castrator/decapitator of the male, dissimulatress or fake, predatory, engulfing mother, preying on male weakness, are all consequences of the ways in which male orgasm has functioned as the measure and representative of all sexualities and all modes of erotic encounter."......(source from some site..dont rememeber)