Tōnalpōhualli

The tōnalpōhualli (Nahuatl pronunciation: ), meaning “count of days” in Nahuatl, is an Aztec version of the 260-day calendar in use in pre-Columbian Mesoamerica. This calendar is neither solar nor lunar, but rather consists of 20 13-day (trecena) periods. Each trecena is ruled by a different deity.

Description

Tonalpōhualli calendar representation

The basis of the tōnalpōhualli is unknown. Several theories have been advanced for this calendrical period: that it represents a Venusian cycle, that it represents the human gestation period, or that it represents the number of days between the zenithal passage of the sun in the tropical lowlands. On the other hand, some scholars including J. E. S. Thompson suggest that the tōnalpōhualli was not based on natural phenomena at all, but rather on the integers 13 and 20, both considered important numbers in Mesoamerica.

The other major Aztec calendar, the xiuhpōhualli, is a 365-day year, based on 18 months of 20 days and five nameless days. A xiuhpōhualliwas designated by the name of its first tōnalpōhualli day. For example, Hernán Cortés met Moctezuma II on the day 8 Wind in the year 1 Reed (or November 8, 1519 in the Julian calendar).

The xiuhpōhualli and the tōnalpōhualli would coincide approximately every 52 years.

Day signs

 

Trecena Glyph Aztec deities associated Cardinal point
1 Cipactli (Caiman or aquatic monster) Cipactli.jpg Tōnacātēcuhtli East
2 Ehēcatl (Wind) Ehecatl2.jpg Quetzalcoatl North
3 Calli (House) Calli.jpg TepēyōllōtlQuetzalcoatl West
4 Cuetzpalin (Lizard) Cuetzpalin.jpg Huēhuecoyōtl or Macuilxōchitl South
5 Cōātl (Snake) Coatl.jpg Chalchiuhtlicue and Tlazōlteōtl East
6 Miquiztli (Death) Miquiztli.jpg Tōnatiuh and Tēcciztēcatl North
7 Mazātl (Deer) Mazatl.jpg Tlāloc and Chicomecōātl or 4 Ehēcatl West
8 Tōchtli (Rabbit) Tochtli.jpg Mayahuel and Xōchipilli or Centeōtl South
9 Ātl (Water) Atl3.jpg Tlahuizcalpantecuhtli or Xiuhtecuhtli East
10 Itzcuintli (Dog) Itzcuintli.jpg Mictlāntēcutli North
11 Ozomahtli (Monkey) Ozomatli.jpg Patecatl and Cuāuhtliocēlōtl West
12 Malīnalli (Grass) Malinalli.jpg Itztlacoliuhqui South
13 Ācatl (Reed) Acatl.jpg Tezcatlipōca or Uactli and Ixcuina or Tlazōlteōtl East
14 Ocēlōtl (Ocelot or Jaguar) Ocelotl.jpg Tlazōlteōtl North
15 Cuāuhtli (Eagle) Cuauhtli.jpg Xīpe Totēuc and Quetzalcoatl West
16 Cōzcacuāuhtli (Vulture) Cozcacuauhtli.jpg Itzpapalotl South
17 Olīn (Movement or Earthquake) Olin (Aztec glyph from the Codex Magliabechiano).jpg Xolotl and Tlālchitōnatiuh or 4 Olīn East
18 Tecpatl (Flint or Knife) Tecpatl.jpg Chalchiuhtotolin North
19 Quiyahuitl (Rain) Quiahuitl.jpg Tōnatiuh West
20 Xōchitl (Flower) Xochitl.jpg Xōchiquetzal and Tezcatlipōca South

Gallery of day signs

Note that the symbols are arranged counterclockwise around the calendar stone.