structural:expansion, stylistic:tone, structural:reformatting, information:filtering
Calendar

The 365-day haab was produced by a cycle of eighteen named 20-day winal s, completed by the addition of a 5-day period called the wayeb. The wayeb was considered to be a dangerous time, when the barriers between the mortal and supernatural realms were broken, allowing malignant deities to cross over and interfere in human concerns. In a similar way to the tzʼolkin, the named winal would be prefixed by a number (from 0 to 19), in the case of the shorter wayeb period, the prefix numbers ran 0 to 4. Since each day in the tzʼolkin had a name and number (e.g. 8 Ajaw), this would interlock with the haab, producing an additional number and name, to give any day a more complete designation, for example 8 Ajaw 13 Keh. Such a day name could only recur once every 52 years, and this period is referred to by Mayanists as the Calendar Round. In most Mesoamerican cultures, the Calendar Round was the largest unit for measuring time.