Zassetsu (Supplementary Solar Terms)
Zassetsu is Japanese original terms that complement 24 Solar Terms.
They were used for farmers to compreghend seasons, and still now they give us a sence of seasons and have a big impact on the seasonal events in Japan.
Here are some of them, which we are familiar with and till strongly connect to our custom.
1.土用(Do-yo)
the perood of 18 days before the beginning of four sesons in 24 solar terms
立春(Risshun - the beginning of spring - approx. 4 Feb)
立夏(Rikka- the beginning of summer - approx. 5 May)
立秋(Risshu- the beginning of autumn - approx. 7 August)
立冬(Ritto- the beginning of winter - approx. 7 November)
＊土用の丑の日(Do-yo no ushi no hi) is the day we have a custom of eating eels.
2.節分(Setsubun)
the day before 立春(Risshun)
＊the day of Bean-throwing tradition
3.彼岸(Higan)
the period of 7days which contains 立春(Risshun) and 立秋(Risshu) in the middle
＊We have a custom to go to our cemetary during this period.
4.八十八夜(Hachi ju hachi ya)
88 days after 立春(Risshun) , which is approx. on 2 May
＊There is a well-known song, saying `Hachi-ju-hachi-ya when summer approaches ...'
5.入梅( Nyubai)
80 degrees in the ecliptic longitude, which is approx. on 11 June
＊It literally means `to enter plums'. As this is the season of plums, we use this term to describe the wet season begins.
Similarly, 梅雨(tsu-yu) means the wet season in Japan. `Plum rain' is its literal meaning.
:Bibliography:
eco.mtk.nao.ac.jp/koyomi/faq/24sekki.html.en