1. lover; sweetheart; boyfriend; girlfriend
Wikipedia definition
2. Significant otherSignificant other (SO) is colloquially used as a gender-blind term for a person's partner in an intimate relationship without disclosing or presuming anything about marital status, relationship status, or sexual orientation, as it is vague enough to avoid offense by using a term that an individual might consider inappropriate (e.g. lover when he considers him a boyfriend, or girlfriend when he considers her a life partner). In the United States the term is sometimes used in invitations, e.g.
Read “Significant other” on English Wikipedia
Read “恋人” on Japanese Wikipedia
Read “Significant other” on DBpedia


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