A lover-in-law is a colloquial term for the partner of one’s own partner. It is a variation of terms like mother-in-law and sister-in-law, which are the mothers and sisters of one’s own partner. The term lover-in-law is most commonly used in the polyamory community, where people tend to have more than one partner.
A person’s lover-in law is sometimes called their metamour.
Many people within the polyamory community have embraced the term lover-in-law because has more emotional connotations than metamour. The term lover-in-law shows a familial connection between people that is greater than simply sharing a partner as a wife and a mistress might, for example. Lovers-in-law usually have a strong emotional connection. They may socialize at parties or even go on group dates with their shared partner.
While a lover-in-law is a partner’s partner, some believe this explanation is quite cumbersome. In this phrase too, the only relationship stated is with the first partner. Lover-in-law emphasizes a relationship with both the original partner, and the partner’s partner. As such, this terms eliminates the idea of competition and suggests a common shared bond that is much more positive.
