domestic partner vs spouse equivalent

domestic partner and spouse equivalent both are nouns.

Word	Noun	Adjective	Verb	Adverb
domestic partner	Yes	No	No	No
spouse equivalent	Yes	No	No	No

As nouns, domestic partner and spouse equivalent are synonyms defined as:

domestic partner and spouse equivalent: a person (not necessarily a spouse) with whom you cohabit and share a long-term sexual relationship

Other synonyms of domestic partner include significant other, spousal equivalent.

domestic partner (noun)	spouse equivalent (noun)
a person (not necessarily a spouse) with whom you cohabit and share a long-term sexual relationship	a person (not necessarily a spouse) with whom you cohabit and share a long-term sexual relationship