In law and in cultural anthropology

Cultural anthropology

Cultural anthropology is a branch of anthropology focused on the study of cultural variation among humans, collecting data about the impact of global economic and political processes on local cultural realities. Anthropologists use a variety of methods, including participant observation,...

, affinity, as distinguished from consanguinity

Consanguinity

Consanguinity refers to the property of being from the same kinship as another person. In that respect, consanguinity is the quality of being descended from the same ancestor as another person...

, is kinship

Kinship

Kinship is a relationship between any entities that share a genealogical origin, through either biological, cultural, or historical descent. And descent groups, lineages, etc. are treated in their own subsections....

 by marriage

Marriage

Marriage is a social union or legal contract between people that creates kinship. It is an institution in which interpersonal relationships, usually intimate and sexual, are acknowledged in a variety of ways, depending on the culture or subculture in which it is found...

. It is the relation which each party to a marriage bears to the kindred of the other. In English, affinity is usually signified by adding "-in-law" to the degree of kinship. In addition to kinship by marriage, "affinity" can sometimes also include kinship by adoption

Adoption

Adoption is a process whereby a person assumes the parenting for another and, in so doing, permanently transfers all rights and responsibilities from the original parent or parents...

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