matrilineal

adj. originating with the mother, of descent through the mother's side of the family

Matrilineality is a system in which one belongs to one's mother's lineage.A matriline is a line of descent from a female ancestor to a descendant (of either sex) in which the individuals in all intervening generations are female. In a matrilineal descent system (uterine descent), an individual is considered to belong to the same descent group as his or her mother. This is in contrast to the more currently common pattern of patrilineal descent. Patrilineal descent systems have not always been so common. Logically, it is easier to identify who the mother of a child is than the father.
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Adjective
1. based on or tracing descent through the female line; "matrilineal inheritance"
(synonym) matrilinear
(similar) lineal, direct