juurokogatsu

Juurokogatsu is a term originating from the Japanese calendar system. It literally translates to "sixteenth month." In traditional Japanese lunisolar calendars, months were often numbered rather than named. Therefore, juurokogatsu would refer to the sixteenth month of such a calendar.

The concept of a sixteenth month suggests a calendar that has been adjusted for astronomical or seasonal discrepancies. Lacking in the standard twelve months of a year, a thirteenth month, often called an intercalary or leap month, was sometimes added to keep the calendar synchronized with the solar year and the seasons. If such a system were in place and extended beyond a single leap month, a sixteenth month would imply a more complex or perhaps a different calendrical system altogether.

It is important to note that the modern Japanese calendar, like most of the world, follows the Gregorian calendar, which has twelve months. The term juurokogatsu is therefore primarily of historical or academic interest, pertaining to older or hypothetical calendrical structures rather than current usage. In contemporary Japan, December is referred to by its specific name, juu-ni-gatsu, meaning "twelfth month." The existence of a "sixteenth month" is not part of any currently observed or widely recognized Japanese calendar.