1. a person who is not related by blood or marriage; someone outside one's family
Usage: often used in anthropology and sociology

1. not related by blood or marriage; unrelated
Usage: used in academic and technical contexts

Examples

• In the study, researchers compared behavior toward kin versus nonkin.
• The tribe maintained strict rules about marriage between kin and nonkin groups.
• She felt more comfortable sharing secrets with nonkin friends than distant relatives.
• Nonkin members of the community were invited to the celebration.
• Anthropologists observed how nonkin relationships formed in the village.
• He treated his adopted siblings as kin rather than nonkin.