How does the Iroquois kinship system classify fathers and their brothers?

In the Iroquois kinship system, the father and his brother are classified using the same term. This is a hallmark of a classificatory system, in which certain collateral relatives—those not in an individual's direct line of descent—are grouped together with lineal kin.1

This specific arrangement is often described by anthropologists as a form of bifurcate merging terminology. In such systems, the terminology reflects the social structure by merging the father with his brother, while typically distinguishing them from the mother's brother, who is referred to by a different term (such as uncle).21

It is important to note that while these individuals share a kin term, this classification is a matter of social and terminological organization rather than a confusion of biological identity; members of the community clearly distinguish between an individual's biological father and other men in that generational cohort.1