The definition of hymen is a membrane partially covering the entrance to the vagina.(noun)
A flap of tissue over the entrance to the vagina that breaks when a girl has sex for the first time is an example of a hymen.
See hymen in Webster's New World College Dictionary
Origin: Gr hymēn, membrane < IE *syumen-, ligature < base *siw- > sew
See hymen in American Heritage Dictionary 4
Origin: Late Latin hymēn
Origin: , from Greek humēn, thin skin, membrane; see syū- in Indo-European roots.
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