Final answer:
Polyandry is a form of marriage where a woman has multiple husbands, and it is a type of polygamy. It is especially rare compared to polygyny, where a man has multiple wives, and is mainly practiced in specific cultures like some areas of Nepal.
Step-by-step explanation:
The form of marriage in which a woman may have multiple husbands is known as polyandry. It is one type of polygamy, which denotes a marital system where individuals are married to more than one partner at the same time. Polyandry is comparatively rare and represents a distinct contrast to polygyny, where one man is married to multiple women. While polygyny is found in many cultures worldwide, polyandry is much less common and is observed in only about 1 percent of the world's cultures.
Fraternal polyandry is a subtype where brothers share a single wife, commonly seen in some areas of Nepal. This practice helps in keeping family land intact, minimizing population growth, and managing scarce resources. Polyandry and polygyny are both found in polygamous societies, although the former is far less prevalent.