Fictive kinship is a term used by
anthropologists and
ethnographers to describe forms of
kinship or social ties that are based on neither
consanguinal (blood ties) nor
affinal ("by marriage") ties, in contrast to
true kinship ties. To the extent that consanguinal 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
fictive, in the sense of
not-real. Invoking the concept as a cross-culturally valid anthropological category therefore rests on the presumption that the inverse category of "(true) kinship" built around consanguinity and affinity is similarly cross-culturally valid. Use of the term was common until the mid-to-late twentieth century, when anthropology effectively deconstructed and revised many of the concepts and categories around the study of kinship and social ties. In particular, anthropologists established that a consanguinity basis for kinship ties is not universal across cultures, and that—on the contrary—it may be a culturally specific symbol of kinship only in particular cultures (see the articles on
kinship and
David M. Schneider for more information on the history of kinship studies).