Seasonality in Japanese Language and Life: Solar Terms, Seasonal Words, and Letter Greetings
Seasonality in Japanese language and life is not best understood as a national temperament. It is better understood as a layered system of four documented conventions: a borrowed solar-term calendar, a literary rule for haiku, an epistolary register for formal letters, and a body of everyday seasonal vocabulary.1 A learner who writes formal Japanese, reads haiku, or shops for seasonal food meets all four layers in turn.
Overview
The reason Japanese seems to carry "so many seasonal words" is that four separate traditions each contribute their own vocabulary. The first is the 二十四節気 (nijūshi sekki), a twenty-four-part solar calendar inherited from China and subdivided into seventy-two microseasons. Its term names are Sino-Japanese 漢語 compounds.1 The second is the 季語 (kigo), the season word that haiku are required to contain.2
The third is the 時候の挨拶 (jikō no aisatsu), the fixed seasonal greeting that opens a formal letter. This layer sits alongside the time-of-day and seasonal greetings a learner meets in speech.3 The fourth is the everyday vocabulary of 旬 (shun), 衣替え (koromogae), and 花見 (hanami) that a learner meets in shops, schools, and conversation.
Each layer is rule-governed and learnable. None of them requires, or supports, the claim that speakers of Japanese are innately attuned to nature; the calendar layer in particular is shared across the East Asian cultural sphere of China, Korea, Vietnam, and Japan.1
The 二十四節気: Japan's 24 Solar Terms
Where the system came from
The 二十四節気 divides the solar year into twenty-four segments by season and climate. UNESCO's inscription locates its origin in the Yellow River region of China. There, the ancient Chinese divided the sun's annual motion into twenty-four segments, each a named solar term passed down across generations.1
The system is more than two thousand years old and spread from China to Korea, Vietnam, and Japan within the East Asian cultural sphere.1 It reached Japan with the calendar around the sixth century, in the Asuka period, and was later revised to fit Japan's own seasons.4
China's "The Twenty-Four Solar Terms" was inscribed on UNESCO's Representative List of the Intangible Cultural Heritage of Humanity in 2016, under a nomination submitted by China.1 Borrowing a calendar and localizing it is ordinary cultural history, shared across the region.
Each term corresponds to a fixed value of the sun's ecliptic longitude, the sun's apparent path across the sky, in fifteen-degree steps. 立春 (risshun) is set at ecliptic longitude 315 degrees, and the year is divided into four seasons with six terms in each.5
The names and the felt weather often diverge. NAOJ notes that 立春 falls around February 4 even though winter conditions persist in many regions; the names mark the season's start on the old reckoning, so they precede the weather.5
The calendar also had a structural job. In the lunisolar 旧暦 (kyūreki, old calendar), the solar terms governed where the leap month (閏月) was inserted. The system survives today as a 農事暦 (agricultural calendar) and a 生活暦 (life calendar) for enjoying 旬.4
The 24 terms at a glance
The eight pivot points are the four season-openers (四立: 立春・立夏・立秋・立冬) and the two solstices and two equinoxes (二至二分: 夏至・冬至・春分・秋分). Each term shifts by roughly a day from year to year, so the dates below are approximate. NAOJ publishes the exact figures for each year in its almanac.6
Spring (春)
| # | Term | Reading | Falls around6 | Literal sense |
|---|---|---|---|---|
| 1 | 立春 | risshun | Feb 4 | start of spring (pivot: 四立) |
| 2 | 雨水 | usui | Feb 19 | rain water (snow turns to rain) |
| 3 | 啓蟄 | keichitsu | Mar 5 | insects awaken from hibernation |
| 4 | 春分 | shunbun | Mar 20 | spring equinox (pivot: 二分) |
| 5 | 清明 | seimei | Apr 5 | pure and bright |
| 6 | 穀雨 | kokuu | Apr 20 | grain rain |
Summer (夏)
| # | Term | Reading | Falls around6 | Literal sense |
|---|---|---|---|---|
| 7 | 立夏 | rikka | May 5 | start of summer (pivot: 四立) |
| 8 | 小満 | shōman | May 21 | lesser fullness (grain plumps) |
| 9 | 芒種 | bōshu | Jun 6 | grain in ear / seeding |
| 10 | 夏至 | geshi | Jun 21 | summer solstice (pivot: 二至) |
| 11 | 小暑 | shōsho | Jul 7 | lesser heat |
| 12 | 大暑 | taisho | Jul 23 | greater heat |
Autumn (秋)
| # | Term | Reading | Falls around6 | Literal sense |
|---|---|---|---|---|
| 13 | 立秋 | risshū | Aug 7 | start of autumn (pivot: 四立) |
| 14 | 処暑 | shosho | Aug 23 | heat abates |
| 15 | 白露 | hakuro | Sep 7 | white dew |
| 16 | 秋分 | shūbun | Sep 23 | autumn equinox (pivot: 二分) |
| 17 | 寒露 | kanro | Oct 8 | cold dew |
| 18 | 霜降 | sōkō | Oct 23 | frost descends |
Winter (冬)
| # | Term | Reading | Falls around6 | Literal sense |
|---|---|---|---|---|
| 19 | 立冬 | rittō | Nov 7 | start of winter (pivot: 四立) |
| 20 | 小雪 | shōsetsu | Nov 22 | lesser snow |
| 21 | 大雪 | taisetsu | Dec 7 | greater snow |
| 22 | 冬至 | tōji | Dec 22 | winter solstice (pivot: 二至) |
| 23 | 小寒 | shōkan | Jan 5 | lesser cold |
| 24 | 大寒 | daikan | Jan 20 | greater cold |
By calendar convention, the solar-term year begins at 立春. For that reason, the early-January terms 小寒 and 大寒 close the cycle and are listed last.4 In any given Gregorian year, they fall in early-to-mid January.6
The 七十二候 microseasons
Each of the twenty-four sekki is subdivided into three roughly five-day periods, giving seventy-two 候 (kō, microseasons). Each kō is named after a brief natural phenomenon: a plant, an animal, or a change in the weather.7
The localization here is documented, not folkloric. The original kō names came from China, but in Japan they were repeatedly revised to match the local climate. The astronomer 渋川春海 (Shibukawa Harumi) established a Japan-adapted set, the 本朝七十二候 (Honchō shichijūni kō), when he implemented the 貞享暦 (Jōkyō calendar) in 1685.7
The seventy-two kō names most often cited today derive from the 略本暦 (ryakuhonreki) of 1874.7 Each reads like a one-line nature observation, as in the first kō of 立春:
東風解凍7
"The east wind melts the ice."
季語: Seasonal Words in Haiku
What a 季語 is and why haiku require one
A 季語 (kigo) is a word that signals a specific season. Including one is the basic formal rule of the 5-7-5 (seventeen-on) haiku.2 The rule is a literary convention with a catalog behind it, not a measure of a poet's sensitivity.
That catalog is the 歳時記 (saijiki), the almanac that collects season words. It organizes them by season and category, usually pairing each word with its meaning and an example haiku.2
The saijiki sorts kigo into five seasons: 春, 夏, 秋, 冬, and 新年 (New Year). Within each season, the words are filed under categories such as 時候 (season and time), 天文 (sky and weather), 地理 (geography), 生活 and 人事 (daily life and human affairs), 行事 (observances), 動物 (animals), and 植物 (plants).2
Figures vary by source. The Kigosai Saijiki publishes a list of roughly 5,000 season words, while popular sources cite figures closer to 8,000.2 Treat the count as a range, not a fixed number.
The most cited haiku in the tradition shows the one-kigo rule in action. Note the historical spelling 飛びこむ, preserved from the 1686 attestation:
古池や蛙飛びこむ水の音8
"An old pond; a frog jumps in, the sound of water."
The 季語 here is 蛙 (kawazu, "frog"), classified as a spring word in the saijiki tradition.8
時候の挨拶: Seasonal Letter Greetings
The 拝啓 ... 敬具 frame
A formal Japanese letter opens with a 頭語 (tōgo, opening word) and closes with a matching 結語 (ketsugo, closing word). The seasonal greeting comes immediately after the 頭語, before the body.93
The canonical pairing is 拝啓 (haikei) to open and 敬具 (keigu) to close. They work as a set: a letter begun with 拝啓 must close with 敬具.3
This is an elevated written register. The 漢語調 (kango-style) openers that end in 〜の候 are long-established Chinese-style formal greetings. They are distinct from colloquial openers such as 「○○の頃となりました」 and are reserved for formal or business correspondence to clients and superiors.93
A complete opening assembles the opening word, the seasonal opener, and a set congratulatory phrase. The July opener 盛夏の候 and the 貴社ますますご清栄… formula below are each verbatim from the source. Putting them together into one sentence follows the standard documented pattern, not a free invention:
拝啓 盛夏の候、貴社ますます御清栄のこととお喜び申し上げます。3
"Dear Sir/Madam, in this height of summer, I am delighted that your company grows ever more prosperous."
Reading 〜の候 and 〜のみぎり openers
Here 候 (こう, kō) means "season" or "time." A season keyword plus 候, as in 盛夏の候, is the standard 漢語調 opener.93 The slot has a more literary variant: a season keyword plus 〜のみぎり (みぎり, "time" or "occasion") fills the same role, as in 盛夏のみぎり.9
These openers are fixed and month-bound. Each month has its conventional set, and pairing the wrong month's opener, or inventing one, reads as an error.93
Seasonal openers by month
The table below gives the verbatim 〜の候 openers for each month from a business letter-writing reference. It also gives the reading of one representative opener and a literal gloss. Several options exist per month, and the right choice can depend on which part of the month the letter is sent.3
| Month | Openers (〜の候)3 | Reading (one representative) | English gloss |
|---|---|---|---|
| 1月 | 新春の候、初春の候、寒冷の候、厳冬の候 | shinshun no kō | "season of the new spring (New Year)" |
| 2月 | 立春の候、晩冬の候、雪解の候、梅花の候 | risshun no kō | "season of the start of spring" |
| 3月 | 早春の候、春分の候、春色の候 | sōshun no kō | "season of early spring" |
| 4月 | 桜花の候、麗春の候、陽春の候、春日の候 | yōshun no kō | "season of warm, bright spring" |
| 5月 | 青葉の候、立夏の候、残春の候、初夏の候 | shoka no kō | "season of early summer" |
| 6月 | 入梅の候、梅雨の候、初夏の候 | nyūbai no kō | "season of the rains' onset" |
| 7月 | 梅雨明けの候、盛夏の候、酷暑の候 | seika no kō | "season of high summer" |
| 8月 | 残暑の候、納涼の候、暮夏の候、晩夏の候 | zansho no kō | "season of lingering late-summer heat" |
| 9月 | 初秋の候、秋分の候、秋晴の候、秋冷の候 | shoshū no kō | "season of early autumn" |
| 10月 | 仲秋の候、秋冷の候、紅葉の候 | kōyō no kō | "season of autumn leaves" |
| 11月 | 紅葉の候、晩秋の候、初冬の候、氷雨の候 | banshū no kō | "season of late autumn" |
| 12月 | 師走の候、霜寒の候、歳晩の候 | shiwasu no kō | "season of December, the priests-run month" |
Some openers track the part of the month, such as 余寒 versus 立春 within February. Treat each as a convention, not the only valid choice, and match the opener to the actual sending date.93
Seasons in Everyday Vocabulary
旬: food at its season
旬 (shun) is the peak season for a produce item or fish: the stretch when it is at its freshest and best. It drives the vocabulary of menus, shop signs, and everyday conversation about food.
秋刀魚は秋が旬です。
"Pacific saury is in season in autumn."
The sentence above is a constructed illustration, not a cited quotation; it models the sense of 旬 as the peak season for a food.
衣替え, festivals, and seasonal customs
衣替え (koromogae) is the conventional twice-yearly wardrobe change between summer and winter clothing. It is keyed to the same seasonal-weather vocabulary of 四季 and 天気.10 The custom came from China and entered Japan as a Heian-period court observance held twice a year, originally called 更衣 (kōi).10
After Japan adopted the Gregorian calendar on January 1, 1873, the convention settled on June 1 for switching to summer clothing and October 1 for switching to winter clothing. Schools and many companies still use those dates for uniforms.10
紅葉狩り (momijigari) is "autumn-leaf viewing." The 狩り ("hunting") extends to seeking out and appreciating seasonal plants and flowers rather than literal hunting; here it names the practice of going to admire the autumn leaves.
This section stays on the seasonal-vocabulary angle. The names of specific observances such as お盆, 正月, 七夕, and 節句 belong with the holidays and festivals material, which a learner can read alongside this one.
桜, 花見, and 桜前線
花見 (hanami, "cherry-blossom viewing") is a real and widely practiced social custom, not a spiritual rite. MAFF traces it to Nara-period aristocratic gatherings, which first viewed imported plum (梅) before shifting to cherry (桜) in the Heian period. The earliest recorded blossom banquet is Emperor Saga's gathering at 神泉苑 in 812, and the modern picnic-style 花見 across social classes took shape in the Edo period.11
週末に公園で花見をしましょう。
"Let's go cherry-blossom viewing in the park this weekend."
The sentence above is a constructed illustration, not a cited quotation; it models 花見 as the social practice MAFF describes.11
桜前線 (sakura-zensen, "cherry-blossom front") is a meteorological forecasting concept. It is the line connecting the forecast and observed first-bloom dates of cherry, primarily ソメイヨシノ (Somei-Yoshino), as blossoming advances northward across Japan.12 It rests on actual observation. 気象庁 (the Japan Meteorological Agency) records first-bloom (開花) and full-bloom (満開) dates against designated standard trees (標本木).12
桜前線 is the media name for the bloom-date map; the underlying first-bloom observation belongs to 気象庁, which tracks it on designated standard trees.12 It describes weather forecasting, not nature worship.
Good to know
もののあわれ is a literary aesthetic, not a personality trait
もののあはれ (mono no aware) is defined in Japanese reference works as the emotion a person feels when moved by nature and human affairs.13 It belongs to a Heian-period literary context and is associated with 『源氏物語』 (The Tale of Genji), where it appears as a norm of contemporary sensibility.13
It became a literary-critical term through 本居宣長 (Motoori Norinaga) in the eighteenth century. His 『源氏物語玉の小櫛』 argued that the essence of the Genji lies in depicting the feeling stirred by nature and human affairs. In doing so, it established an aesthetic standard separate from the moralistic Confucian and Buddhist view of literature.13
For a learner, the takeaway is to treat もののあはれ as a critical tradition you can study, with a documented history, not an innate "Japanese sensitivity to nature." Read that way, it counters the Orientalizing framing the term often attracts. It uses the same myth-busting lens that reading between the lines of implicit communication demands.13
The calendar is borrowed, and that is normal
The 二十四節気 originated in China's Yellow River region. It is over two thousand years old and spread to Korea, Vietnam, and Japan. UNESCO inscribed China's "Twenty-Four Solar Terms" in 2016.1 It reached Japan with the calendar around the sixth century and was adapted to Japan's climate, as the revision of the 七十二候 shows.74
Borrowing a calendar and adapting it to local conditions is ordinary cultural history. It is not evidence of a unique national bond with nature.
Why the names feel a season early
The four season-openers (立春・立夏・立秋・立冬) name the start of a season on the solar-term reckoning, set by the sun's ecliptic longitude. For that reason, they arrive before the felt weather: 立春 falls around February 4 while it still feels like winter, and 立秋 falls around August 7 in peak heat.5 A learner who reads 立春 as "mid-spring" has the wrong mental model.
The correct reading is that 立 marks a season's beginning; the midpoints are the solstices and equinoxes (二至二分).54
立春は暦の上での春の始まりだ。
"Risshun is the calendrical start of spring."
Letter openers are formulae, not free composition
The 〜の候 openers are fixed by month. Using the wrong month's opener, or inventing one, reads as an error, and the opener must be paired with the matching 頭語 and 結語 set, 拝啓 and 敬具.93
Closing a 拝啓 letter with かしこ, or opening a January letter with the high-summer 盛夏の候, both break the convention. A correct January frame runs 拝啓 … 寒冷の候 … 敬具. 拝啓 and 敬具 form a fixed pair, and each month has its own conventional opener in the elevated written 漢語調 register.93
See also
- Japanese Speech Levels: Plain, Polite, Formal, and Literary Register
- Keigo (敬語): A Complete Cultural Introduction to Japanese Honorific Language
- Bowing, Business Cards, and Greetings: The Body-Language Layer of Japanese Etiquette
- Tatemae and Honne: Public Stance vs. Private Opinion in Japanese
- Time, Date, and Calendar Vocabulary in Japanese