exogamy vs matrimony

exogamy and matrimony both are nouns.

Word	Noun	Adjective	Verb	Adverb
exogamy	Yes	No	No	No
matrimony	Yes	No	No	No

As nouns, matrimony is a hypernym of exogamy; that is, matrimony is a word with a broader meaning than exogamy:

exogamy: marriage to a person belonging to a tribe or group other than your own as required by custom or law
matrimony: the state of being a married couple voluntarily joined for life (or until divorce)

Other hypernyms of exogamy include marriage, spousal relationship, union, wedlock.

exogamy (noun)	matrimony (noun)
marriage to a person belonging to a tribe or group other than your own as required by custom or law	the ceremony or sacrament of marriage
	the state of being a married couple voluntarily joined for life (or until divorce)