personal guardian spirit believed by some Mesoamerican Indians to reside in an animal (animal worship), such as a deer, jaguar, or bird. In some areas the nagual is the animal into which certain powerful men can transform themselves to do evil; thus, the word derives from the Nahuatl word nahualli (“disguise”), applied to the animal forms magically assumed by sorcerers.

The person who is to receive his nagual traditionally goes to an isolated spot and sleeps there; the animal that appears in his dreams or that confronts him when he awakens will thereafter be his particular nagual. Among many modern Mesoamerican Indians, it is believed that the first creature to cross over the ashes spread before a newborn baby becomes that child's nagual. The belief in nagualism varies from region to region. In some areas it is believed that only the most powerful leaders (usually men) possess naguals. In others, all or most people have personal animal guardian spirits.