Eponym:

The term hymen stems from the Latin hymen, which was borrowed from the Greek word “hymḗn” or “ὑμήν,” meaning membrane (of any kind). [1] The latin term “hymen” was used from the 1st and 2nd centuries CE to refer to the anatomical feature, specifically. [1] The Greek word, however, was derived from the Greek god of marriage, Hymenaeus. [1] As such, the name of this anatomical feature indirectly stems from Hymenaeus, making this an eponym that originates from mythology, or a mythonym. 

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