noun
three-person marriage; three-way relationship
Rare term for a marriage or domestic partnership involving three people, often implying a sexual relationship. Can refer to polyamorous arrangements or ménage à trois.
三人婚は、法律上は認められていない。
Three-person marriage is not legally recognized.
その小説では、三人婚の生活が描かれている。
The novel depicts a life of a three-way marriage.
重婚 (bigamy) refers to marrying someone while already legally married to another person, which is illegal. 三人婚 is a consensual three-person relationship, not necessarily involving legal marriage.
ポリアモリー (polyamory) is a broader term for consensual non-monogamous relationships, while 三人婚 specifically denotes a three-person marriage-like union.
Compound of 三人 (three people) and 婚 (marriage). The term is a modern coinage reflecting non-traditional relationship structures.