Which term refers to the practice of having more than one sexual or marriage partner simultaneously?

The term that refers to the practice of having more than one sexual or marriage partner simultaneously is polygamy. This term encompasses various forms of relationships that include multiple partners and is commonly understood as involving either multiple wives or husbands.

Polygamy can be further divided into two subcategories: polygyny, which is when a man has more than one wife, and polyandry, where a woman has more than one husband. This distinction is important in understanding how various cultures may structure relationships.

In contrast, monogamy refers to a marriage or relationship between two individuals only, which is the prevalent form in many societies today. Divorce is entirely unrelated to the concept of having multiple partners as it pertains to the legal dissolution of a marriage. Thus, polygamy accurately captures the essence of having multiple partners concurrently, making it the correct choice.