noun
first Day of the Rat of the New Year
Traditional Japanese calendar term. The first Day of the Rat (子の日) in the new year, associated with customs like gathering young pines and celebrating longevity.
初子の日には、若菜を摘む風習がある。
On the first Day of the Rat of the New Year, there is a custom of picking young greens.
noun
first Day of the Rat of the month (esp. the 11th month)
More general use: the first Day of the Rat in any month, but especially noted for the 11th month in traditional contexts. Rare outside historical or cultural references.
旧暦11月の初子は、特別な祭りの日とされていた。
The first Day of the Rat in the 11th month of the old calendar was regarded as a special festival day.