monandry vs matrimony

monandry and matrimony both are nouns.

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

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

monandry: the state of having only one husband at a time
matrimony: the state of being a married couple voluntarily joined for life (or until divorce)

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

monandry (noun)	matrimony (noun)
the state of having only one husband at a time	the ceremony or sacrament of marriage
	the state of being a married couple voluntarily joined for life (or until divorce)