Significant other

Person's partner in an intimate relationship

The term "significant other" (SO) has different uses in psychology and in colloquial language. Colloquially, "significant other" is used as a gender-neutral term for a person's partner in an intimate relationship without disclosing or presuming anything about marital status, relationship status, gender identity, or sexual orientation. Synonyms with similar properties include sweetheart, other half, better half, spouse, domestic partner, lover, paramour, soulmate, and life partner.

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