What does exogamy mean?
Exogamy is the social rule or practice of marrying outside one's own group — whether that group is defined by clan, lineage, tribe, village, caste, or religion. It stands in direct contrast to endogamy, which requires marriage within the group. Anthropologists have long studied exogamy because it shapes alliances between communities: by compelling people to seek partners elsewhere, it builds networks of kinship and exchange across social boundaries. The term also appears in biology, where it describes reproduction between genetically unrelated individuals, a pattern associated with greater genetic diversity. Commonly discussed forms include clan exogamy and village exogamy, both well attested in societies from Aboriginal Australia to parts of South Asia. Exogamy is a formal, scholarly word, encountered mainly in academic writing, yet it captures a phenomenon central to human social organisation — how communities decide who may marry whom, and what those decisions mean for the ties that bind societies together.
The custom of marrying outside one's own social group, clan, or community.
"Clan exogamy obliged every member to take a spouse from another lineage."
Used almost exclusively in academic contexts such as anthropology and sociology.
In biology, the union of gametes from individuals who are not closely related.
"Exogamy within the population helped maintain healthy levels of genetic variation."
Rarely used in the plural; the uncountable singular is standard, since exogamy denotes a practice or system rather than countable instances.
"The ethnographer compared the exogamies of several neighbouring peoples."
In many Aboriginal Australian and Native American societies, you couldn't marry someone from your own clan even if they were a total stranger — but your cousin from another clan was perfectly acceptable.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of exogamy
The word exogamy was coined in the 19th century from Greek roots: 'exo-', meaning 'outside', and 'gamos', meaning 'marriage'. It emerged as anthropologists of the Victorian era sought precise terminology for marriage customs observed across world cultures, alongside its counterpart endogamy (from Greek 'endon', 'within'). Related words sharing the 'gamos' root include monogamy, polygamy, and bigamy, while the adjective form exogamous derives directly from it.
Related word forms
How exogamy is actually used
A formal, technical term used chiefly in anthropology, sociology, and biology; rare in everyday conversation. It carries no strong emotional connotation and is typically used descriptively rather than prescriptively.
Easily confused with exogamy
Endogamy is the opposite practice — marriage within one's own social group — whereas exogamy is marriage outside it.