Kapu is the ancient Hawaiian code of conduct of laws and regulations. The kapu system was universal in lifestyle, gender roles, politics and religion. An offense that was kapu was often a capital offense, but also often denoted a threat to spiritual power, or theft of mana. Kapus were strictly enforced.

Breaking one, even unintentionally, often meant immediate death, "Koʻo kapu". The concept is related to taboo and the tapu or tabu found in other Polynesian cultures. The Hawaiian word kapu is usually translated to English as "forbidden", though it also carries the meanings of "keep out", "no trespassing", "sacred", "consecrated", or "holy".

This law stated that men and women could not eat together. Some foods were illegal for women to eat: pork, bananas, taro, coconuts, breadfruit, and certain types of fish because they were all foods representing the gods. Some Kapu's did not allow women to regulate the building of a house, a canoe, or heiau, birth and death ceremonies, and many other activities.

This law has been used until 1819 where King Liholiho, his mother Queen Keōpūolani and his father's other queen Kaʻahumanu abolished this law. This was one of the biggest changes in Hawaii and its culture, but also making other Hawaiians today to eat with their family and friends without being killed.

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