A matronymic is a personal name based on the given name of one's mother, grandmother, or any female ancestor. It is the female equivalent of a patronymic. Around the world, matronymic surnames are far less common than patronymic surnames.

In some cultures in the past, matronymic last names were often given to children of unwed mothers. Or if a woman was especially well known or powerful, her descendants might adopt a matronym based on her name. A matronymic is a derived name, as compared to a matriname, which is an inherited name from a mother's side of the family, and which is unchanged.

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