a term referring to people in committed relationships, where typically both individuals within said relationship also enjoy casual sex with other people, typically, but not exclusively, with other people in committed relationships that are also into swinging. People who enjoy swinging are known as swingers.

Swinging is a form of open relationship and non-monogamy that should not be confused with polyamory. Although polyamorous relationships may also engage in swinging, the key difference between polyamory and swinging is that swinging is not based on seeking out love: although swingers may enjoy loving and affectionate bonds with those they swing with, it is not about seeking out committed, romantic and/or emotional bonds with more than one person (as in polyamory), as much as it is seeking out sexual activity. It is not seeking out an extension to the current relationship or an extra participant in the relationship; the committed relationship is separate from the sexual relationship enjoyed with other people.

For this reason, it has also been commonly known as wife swapping, husband swapping or partner swapping.