A trecena is a 13-day period used in

pre-Columbian In the history of the Americas, the pre-Columbian era spans from the original settlement of North and South America in the Upper Paleolithic period through European colonization, which began with Christopher Columbus's voyage of 1492. Usually, th ...

Mesoamerican calendars Mesoamerican calendars are the calendrical systems devised and used by the pre-Columbian cultures of Mesoamerica. Besides keeping time, Mesoamerican calendars were also used in religious observances and social rituals, such as for divination. T ...

. The 260-day

calendar A calendar is a system of organizing days. This is done by giving names to periods of time, typically days, weeks, months and years. A date is the designation of a single and specific day within such a system. A calendar is also a physi ...

(the '' tonalpohualli'') was divided into 20 trecenas. Trecena is derived from the Spanish chroniclers and translates to "a group of thirteen" in the same way that a dozen (or in Spanish ''docena'') relates to the number twelve. It is associated with the

Aztec The Aztecs () were a Mesoamerican culture that flourished in central Mexico in the post-classic period from 1300 to 1521. The Aztec people included different Indigenous peoples of Mexico, ethnic groups of central Mexico, particularly those g ...

s, but is called different names in the

s of the

Maya Maya may refer to: Civilizations * Maya peoples, of southern Mexico and northern Central America ** Maya civilization, the historical civilization of the Maya peoples ** Maya language, the languages of the Maya peoples * Maya (Ethiopia), a populat ...

, Zapotec,

Mixtec The Mixtecs (), or Mixtecos, are indigenous Mesoamerican peoples of Mexico inhabiting the region known as La Mixteca of Oaxaca and Puebla as well as La Montaña Region and Costa Chica Regions of the state of Guerrero. The Mixtec Culture wa ...

, and others of the region. Many surviving Mesoamerican codices, such as

Codex Borbonicus The Codex Borbonicus is an Aztec codex written by Aztec priests shortly before or after the Spanish conquest of the Aztec Empire. It is named after the Palais Bourbon in France and kept at the Bibliothèque de l'Assemblée Nationale in Paris. The ...

, are divinatory calendars, based on the 260-day year, with each page representing one trecena.

See also