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polyamorous vs. polygamous

polyamorous

[pol-ee-am-er-uhs] / ˌpɒl iˈæm ər əs /

adjective

noting or relating to polyamory, the practice or condition of participating simultaneously in more than one serious romantic or sexual relationship with the knowledge and consent of all partners.

polygamous

[puh-lig-uh-muhs] / pəˈlɪg ə məs /

adjective

of, pertaining to, characterized by, or practicing polygamy; polygamic.
Botany. bearing both unisexual and hermaphrodite flowers on the same or on different plants of the same species.