MATRONYMIC

A 'matronymic' is a personal name based on the name of one's mother. It is the female equivalent of a patronymic. In patriarchal societies matronymic surnames are far less common than patronyms. In the past matronymic last names were often given to children of unwed mothers. In Russia, Ukraine, and Belarus a person whose father is unknown receives a matronym. Other times when a woman was especially well known or powerful her descendants would adopt a matronym based on her name. Today some have chosen to adopt matronymic last names, such as the poet Yocheved Bat-Miriam.
Some English matronyms are Beaton, Hilliard, and Megson.
Family names derived from matronyms are also found in Romania, especially in the region of Moldavia. Examples include: Aioanei, Ababei, Acatrinei, Ailincăi.
Some Icelandic people, like Heiðar Helguson, have matronyms. See Icelandic name.
Matronymics also appear in medieval Irish and Welsh tales such as Cath Maige Tuired and the Fourth Branch of the Mabinogi (the children of Dôn).