Incest is sexual intercourse between family members and close relatives. The term may apply to sexual activities between: individuals of close "blood relationship"; members of the same household; step relatives related by adoption or marriage; and members of the same clan or lineage.The incest taboo is and has been one of the most common of all cultural taboos, both in current nations and many past societies. Most modern societies have laws regarding incest or social restrictions on closely consanguineous marriages.
