taboo or tabu, prohibition of an act or the use of an object or word under pain of punishment. Originally a Polynesian word, taboo can apply to the sacred or consecrated or to the dangerous, unclean, and forbidden. A taboo can be placed on an object, person, place, or word that is believed to have inherent power above the ordinary. This power, called mana, can only be approached by special priests. To give distinction to special moments in the life cycle, taboos are often declared at births, deaths, initiations, and marriages. Taboos are commonly placed on a clan's ancestral guardian, called the totem. The breaking of a taboo usually requires extermination of the offender or some sort of ceremonial purification in order to remove the taint from the community. Often the mana of a taboo is so great that the offender will suffer punishment, even death, merely through fear of its powers.

Prohibition against touching, saying, or doing something for fear of immediate harm from a supernatural force. The term is of Polynesian origin and was first noted by Capt. James Cook during his 1771 visit to Tonga, but taboos have been present in virtually all cultures. They may include prohibitions on fishing or hunting at certain seasons, eating certain foods, interacting with members of other social classes, coming into contact with corpses, and (for women) performing certain activities during menstruation. Although some taboos can be traced to evident risks to health and safety, there is no generally accepted explanation of most others; most authorities agree that they tend to relate to objects and actions that are significant for the maintenance of social order.

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