Wayob is the plural form of (or), a Maya word with a basic meaning of 'sleep(ing)', but which in Yucatec Maya is a term specifically denoting the Mesoamerican nagual, that is, a person who can transform into an animal while asleep in order to do harm, or else the resulting animal transformation itself. Already in Classic Maya belief, way animals, identifiable by a special hieroglyph, had an important role to play.
In Yucatec ethnography, the animal transformation involved is usually a common domestic or domesticated animal, but may also be a ghost or apparition, for example 'a creature with wings of straw mats'. Moreover, in the 16th century, wild animals such as jaguar and grey fox are mentioned as animal shapes of the sorcerer, together with the or 'underworld transformer'. Some sort of 'devil's pact' seems to be implied. The Yucatec has its counterparts among other Maya groups. In Tzotzil ethnography, the (here called or chanul) is more often an animal companion and refers not only to domestic animals, but also to igneous powers such as meteor and lightning. In Tzeltal Cancuc, the animal companion is considered a 'caster of disease'. Other names found are:,, or, and or .[1]
A Classic Maya hieroglyph is read as by Houston and Stuart. These authors assert that a glyph representing a stylised, frontal 'Ahau' (Ajaw) face half covered by a jaguar-pelt represents the, with syllabic and elements attached to the main sign clarifying its meaning. Many animals are distinguished by (i) a shoulder cape or scarf tied in front; (ii) a splashing of jaguar spots or other jaguar characteristics; (iii) the attribute of an upturned 'jar of darkness'; and (iv) fire elements.[2]
The Classic include a far wider array of shapes than the 20th-century ones from Yucatán (insofar as the latter have been reported), with specific names assigned to each of them. They include not only many mammals (especially jaguars) and birds, but also apparitions and spooks: hybrids of deer and spider monkey, walking skeletons, a self-decapitating man, a young man within a fire, etc. The animal are likely to be transformative shapes of human beings, the walking skeletons (Maya Death Gods) more particularly of the transformers.
At times, the name of the is followed by an 'emblem glyph' giving the name of a specific Maya kingdom (or perhaps its ruling family). The skeletal prominent on a Tonina stucco wall carries the severed head of a defeated opponent.