Before revision: Matrilateral cross-cousin marriage (mother's brother's daughter marriage) is typically used by anthropologists to describe a form of marriage in which the sons of one kin group marry the daughters of the kin group from which their mother originates.
After revision: Matrilateral cross-cousin marriage is typically used by anthropologists to describe a form of marriage in which the sons of one kin group marry the daughters of the kin group from which their mother originates.