Fictive kinship

Anthropological concept

Fictive kinship (less often, fictional kinship) is a term used by anthropologists and ethnographers to describe forms of kinship or social ties that are based on neither consanguineal (blood ties) nor affinal ("by marriage"), nor nursery (milk) ties. It contrasts with true kinship ties. To the extent that consanguineal and affinal kinship ties might be considered real or true kinship, the term fictive kinship has in the past been used to refer to those kinship ties that are fictional, in the sense of not-real.

From Wikipedia, under CC BY-SA. More on occurri.