Avuncular

The avunculate, sometimes called avunculism or avuncularism, is any social institution where a special relationship exists between an uncle and his sisters' children. This relationship can be formal or informal, depending on the society. Early anthropological research focused on the association between the avunculate and matrilineal descent, while later research has expanded to consider the avunculate in general society.

The term avunculate comes from the Latin , the maternal uncle.

The 1989 Oxford English Dictionary defines "avunculate" as follows:

An avunculocal society is one in which a married couple traditionally lives with the man's mother's eldest brother, which most often occurs in matrilineal societies. The anthropological term "avunculocal residence" refers to this convention, which has been identified in about 4% of the world's societies.

This pattern generally occurs when a man obtains his status, his job role, or his privileges from their nearest elder matrilineal male relative. When a woman's son lives near her brother, he is able to more easily learn how he needs to behave in the matrilineal role he has inherited.

According to the Kazakh common law, the avunculate nephews could take anything from the relatives of the mother up to three times. In the Kyrgyz past a nephew, at a feast at his maternal uncle or grandfather, could take any horse from their herd or any delicacy.

In the Southwest United States, the Apache tribe practices a form of this, where the uncle is responsible for teaching the children social values and proper behavior while inheritance and ancestry is reckoned through the mother's family alone. Modern day influences have somewhat but not completely erased this tradition.

The Chamorros of the Mariana Islands and the Taíno of Turks and Caicos Islands are examples of societies that have practiced avunculocal residence.

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