Matronymic

From Freepedia

A matronymic is a personal name based on the name of one's mother. It is the female counterpart to patronymic. In patriarchal societies matronymic surnames are far less common than patronyms. It the past matronymic last names were often given to children of un-wed mothers. Other times when a woman was especially well known or powerful her descendents 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.