Polyandry and polygamy are not totally the same. They have some similarities and they also have their differences. Both polygamy and polyandry are two types of marriages. Polygamy is a type of marriage in which a partner can have more than one spouse. Polygamy is divided into polyandry and polygyny. Polyandry is a type of marriage in which a woman gets married to more than one husband. While polygyny is a type of marriage in which a man gets married to more than one wife.
Polyandry is like a subset to polygamy. Polygamy is widely practiced in most parts of the world. If we should consider the differences using religion, some religions support polygamy, while some frown at it. A number of religions do not really support polyandry. They consider a woman not to be morally fit to be having more than one husband. Polyandry is mostly practiced in countries like Nepal.