Как по Английски будет polygamie

In the linnaean artificial system: the twenty-third class of plants, comprising those that bear both hermaphrodite and unisexual (male or female) flowers, on the same or different plants; (also) any of the orders of the class syngenesia that comprise plants bearing inflorescences composed of many florets (as in plants of the family asteraceae (compositae)).

The practice or custom of having more than one wife or husband at the same time.