The clitoris rivals the penis in size.
"The vaginal wall is, in fact, the clitoris," said Dr O'Connell, who is based in Melbourne.
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"There's nothing quite like the shape of a clitoris," she said.
"The glans are dense with nerve endings and receptors - all the vibration and sensation is there."
The bulk of it is shaped like a pyramid, she said.
Its base forms the external genitalia or vulva; its triangular "walls" are wrapped around the urine-carrying tube known as the urethra and the vagina.
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When aroused, the whole structure becomes engorged.
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