Kin Groups and Descent. The fundamental unit of Iban society is the bilik-family, a group of five or six persons defined by kinship and affinity. Depending upon negotiations at a couple's marriage, there is an almost even chance that their children will be born into the family of either the wife or the husband. Iban families are part of a widely ramifying kinship system that developed in response to Iban mobility. The suku juru and kaban belayan correspond to the kindred. The former connotes kin ties originating with one's grandparents and includes persons to the degree of first cousin. The latter is any group of people who share rights of reciprocity with an Iban, and may include nonkin and even non-Iban. More inclusive groups include "the brotherhood" and "food sharers," made up of distant kin who would be invited to one's festivals, or whose festivals an Iban would attend. Attachment is ambilateral and descent is ambilineal. Although some Iban are capable of reconstructing genealogies up to fifteen generations in depth, such reconstructions are selective and illustrate the Iban practice of "genealogizing" so as to establish ancestral ties with strangers.
Kinship Terminology. Terms of reference are Eskimo and the terms of address are Hawaiian.