In ancient Japan, every month had a poetic name connected to nature, rituals, and seasonal life.
December was called Shiwasu (しわす / 師走) — and unlike most old month names, this one is still commonly used today in modern Japanese, especially to describe the busy feeling of the year’s end.
You can still find this old name printed on traditional calendars, business notices, and even everyday conversation.
Meaning of Shiwasu (しわす / 師走)
The word breaks down as:
- 師 (shi) – “teacher,” “master,” or “priest”
- 走 (wasu / hashiru) – “to run”
Together, Shiwasu is often interpreted as:
“The month when even the teachers (or priests) run.”
In other words, a month so busy that even calm, respected figures have to rush around.
Why is December called “the month when teachers run”?
There are several theories, but the most famous one is:
1. Priests rushing to perform year-end rituals
At the end of the year, Buddhist priests would visit many households to chant sutras, pray, and perform purification rituals.
Because of this, they were constantly traveling — literally running around to complete all the requests before the year ended.
2. A symbol of universal year-end busyness
Over time, the meaning expanded.
December became known as a month when:
- everyone is busy finishing work
- families prepare for New Year’s
- shops become crowded
- people rush to clean their homes
Even today, Japanese people use Shiwasu to express the special chaos and excitement of December.
Cultural Meaning
Shiwasu carries a unique feeling in the Japanese year. It symbolizes:
- Year-end rush and responsibilities
- Final efforts before the new year begins
- Cleaning and purification
- Reflection on the past year
- Warm anticipation of New Year’s traditions
The word blends both nostalgia and motion — a sense that time suddenly speeds up as the year closes.
Originally inspired by Chinese traditions
As with other traditional month names, Shiwasu was originally influenced by ancient Chinese calendar traditions.
But over centuries, Japan gave the name:
- a uniquely Japanese interpretation
- strong cultural meaning
- emotional nuance still felt today
This makes Shiwasu one of the most familiar and beloved traditional month names, even in the modern era.