An Incest taboo is any cultural

Culture

Culture is a term that has many different inter-related meanings. For example, in 1952, Alfred Kroeber and Clyde Kluckhohn compiled a list of 164 definitions of "culture" in Culture: A Critical Review of Concepts and Definitions...

 rule or norm that prohibits practices of sex

Sex

In biology, sex is a process of combining and mixing genetic traits, often resulting in the specialization of organisms into a male or female variety . Sexual reproduction involves combining specialized cells to form offspring that inherit traits from both parents...

ual relations between relatives. All human cultures have norms regarding who is considered suitable and unsuitable sexual and/or 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...

 partners, and usually certain close relatives are excluded as possible partners. However, there is little agreement among cultures, about which types of blood relations are permissible partners and which are not.