WordNet: endogamy, inmarriage, intermarriage

marriage within one's own tribe or group as required by custom or law

• hypernym marriage, matrimony, spousal relationship, union, wedlock

endogamy

• (englanti) exogamy (antonym)

• (englanti) endogamous (derivationally related)
• (suomi) endogamia (synonyymi)

inmarriage

• (englanti) inmarry (derivationally related)
• (suomi) sisäryhmäavioliitto (synonyymi)

intermarriage

• (englanti) intermarry (derivationally related)
• (suomi) sisäryhmäavioliitto (synonyymi)