Trecena
![](https://upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Codex_Borbonicus_%28p._13%29.jpg/300px-Codex_Borbonicus_%28p._13%29.jpg)
Depiction of the 13th Trecena in Codex Borbonicus
Trecena is the name of a thirteen-day unit of time that was used in the Mesoamerican calendar system . Even if the Trecena is largely associated with the Aztec culture today, this unit of time was also used in the calendars of the Maya , Zapotec , Mixtec , Olmec and other cultures. The name Trecena is derived from the Spanish word for thirteen ( trece ).
A Trecena is one twentieth of the day 260, ceremonial Tonalpohualli Calendar info Aztec represents Maya and its equivalent, the Tzolkin . Each of the twenty Trecenas is associated with one or more deities.