Polygamy Polygyny Polyandry

 Polygamy in the generic term for people who have multiple marriages. 

The most common form of polygamy is polygyny--one man has two or more wives. 

Polyandry is the form of polygamy in which a woman is married to two or more men.

Bigamy refers to a person being married to two people.

Polygamy is rare but more common in some parts of the world than others.

In many countries, polygamy is illegal but some people living in polygamous relationships may have multiple marriages in accordance with their religion.

Polyamory

Polyamory is a multiperson romantic relationship among adults, which usually includes sexual relations. 

Polyamorous relationships are based on consent.

Polyamory differs from polygamy because polygamy includes multiple marriages.

Moors et al. (2021) reported on findings from a national sample in the United States.

Results show that 1 out of 6 people (16.8%) desire to engage in polyamory, and 1 out of 9 people (10.7%) have engaged in polyamory at some point during their life. Approximately 1 out of 15 people (6.5%) reported that they knew someone who has been or is currently engaged in polyamory. Among participants who were not personally interested in polyamory, 1 out of 7 (14.2%) indicated that they respect people who engage in polyamory.

Reference

Moors AC, Gesselman AN and Garcia JR (2021) Desire, Familiarity, and Engagement in Polyamory: Results From a National Sample of Single Adults in the United States. Frontiers in Psychology, 12:619640. doi: 10.3389/fpsyg.2021.619640

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