The hymen (or maidenhead) is a membrane which completely or partially occludes the vaginal opening in human females. The term comes from a Greek word meaning "membrane". Because sexual activity would usually puncture this membrane, its presence has been considered a guarantor of virginity in societies that place a high value on female chastity before marriage.

Nonetheless, the hymen is often lost during childhood in the course of normal physical activities such as bike riding, gymnastics, or sometimes falling down the wrong way; it is also possible for the hymen to break while using tampons. Some women can engage in sexual intercourse without the hymen breaking; some are born with no hymen at all, others with closed hymens that require a medical procedure to allow menstruation, while others have overly thick hymens that may require a gynecologist to break the hymen to prevent pain for the woman during sex, a procedure called a hymenotomy. For these and many other reasons, the hymen should not be used as evidence for or against one's chastity or virginity.

Sometimes a woman has the hymen surgically restored in order to feign virginity.


Hymen is also an alternate name for the Greek goddess Hymenaios.