Definition - What does Nonexclusive Monogamy mean?
Nonexclusive monogamy refers to a two person marriage in which each partner is allowed to engage in sexual relationships outside of the marriage, but not have any other spouses. In some cases, the rules of the particular couple may dictate that, while sexual activity is permitted, emotionally intimate relationships are not.
Kinkly explains Nonexclusive Monogamy
This term can be confusing for people because it describes what many consider "nonmonogamy." However, the use of the term monogamy here is in relation to the marriage, of which there may only be one, rather than in relation to sexual partners.