Marriage is more complicated than most of us realize!

In the field of anthropology, polygamy is defined as the custom of having more than one spouse at the same time; however, if one has two spouses, it is called bigamy so it may be safely assumed that since poly (in this case) means “many”, then polygamy etymologically means “many marriages” or a “multitude of marriages”. Of course, monogamy refers to the marriage of “one spouse” at a time.
Be aware that polygamy does not necessarily mean being married to several women or having several wives. It could also refer to a woman who is married to several men or who has a multitude of husbands; also known as polyandry.
In the field of zoology, polygamy refers to animal mating (male or female) in which an individual mates with more than one animal during any single breeding season. In biology, the mating of a single male with several females or the presence of many queens within a single colony of social insects is called “polygyny“.
On the other hand, when a male mates with just one female or there is only one queen in a colony of social insects, it is called “monogyny”; or if with a few females, “oligogyny.” Of course, in these situations, marriage (gamy) is not relevant to what we consider marriage among humans.

Whoever thinks marriage is a 50-50 proposition doesn't know the half of it.