Lesson 10 · こよみ — the calendar

Seven planets, twelve numbers

Japanese names its days after the planets and numbers its months. Arabic does the exact opposite — it numbers its days and borrows names for its months. Between them the two languages cover the whole calendar twice, and neither invented any of it.

≈20 minutes · every reading checked against Jisho.org · the calendar history from National Astronomical Observatory of Japan and the National Diet Library

Nine lessons have been about characters. This one is the first about words you will need on a Monday — and it arrives with the first kanji in the course, because the days of the week cannot be written without them.

1.Each language numbers the half the other names

Before any vocabulary, the shape of the thing. There are two ways a language can label a repeating cycle: give each slot a name, or count. Japanese and Arabic each do one for days and the other for months — and they disagree about which is which.

English numbers neither, which is why it is the hardest of the three to learn and why you had to memorise thirty days hath September as a child. Japanese months cost you nothing: if you can count to twelve, you know all of them by the end of section 4.

2.The seven days are the seven planets

Every weekday is one character plus 曜日 yōbi. Change the character, change the day — that is the whole system. The character names one of the seven bodies the ancient world could see moving against the stars.

Tap any word to hear it. The middle column is the sky; read straight down it and you have the classical planetary order, which is also the order of the Japanese week.

The Arabic column is the mirror. الْأَحَد is literally the first, الْاِثْنَيْن the second, and the count runs to الْخَمِيس, the fifth. Then it stops: الْجُمُعَة is the gathering and السَّبْت is the rest. Both languages break their own pattern at exactly the point where the week stops being arithmetic and starts being about what people do.

3.Japan had the names for a thousand years before it had the week

This is the part that makes the seven names stick, because it explains why they are astrological rather than practical.

• 806. The monk 空海 Kūkai returns from Tang China with over 460 volumes of esoteric Buddhist texts. Among them is the 宿曜経 Sukuyōkyō, an Indian astrology manual translated into Chinese by Amoghavajra around 759. It carries the seven luminaries — and with them, the names of the seven days.
• Heian period. The court calendar, 具注暦, prints the day of the week beside each date — not to organise the working week, but to tell you whether the day is lucky. Fujiwara no Michinaga's diary 御堂関白記 records the weekday every day. Sunday was sometimes written 密 instead: a transcription of Sogdian Myr, the god Mithra, picked up somewhere along the road from Babylon.
• Until 1876. Nobody rested on Sunday, because there was no week to rest in. Government offices closed on days containing a 1 or a 6 — the 1st, 6th, 11th, 16th, 21st and 26th — a system called 一六日 ichirokubi, fixed by decree in 1868.
• 12 March 1876. Cabinet Order No. 27 makes Sunday a full holiday and Saturday a half-day, effective that April. The names were a thousand and seventy years old; the week itself was new.

The 1876 date and the 一六日 system it replaced are taken from the National Astronomical Observatory of Japan's calendar wiki, which cites the original decrees held by the National Diet Library. It is worth reading over the usual textbook line: the popular claim is simply “Japan adopted the week in 1876”, and the interesting fact — that the names had been in continuous use since 806 — gets lost.

4.Twelve months, twelve numbers

A month is the number plus 月 gatsu. That is the entire rule, and it has three exceptions — all three because the month names entered Japanese from Chinese as one fixed block, long before よん, なな and きゅう became the normal way to count.

Arabic goes the other way and borrows names. يَنايِر, فِبْرايِر, مارِس are Latin months in Arabic clothing, used across Egypt, Sudan, Yemen and the Gulf. Iraq and the Levant keep an older set entirely — كانُون الثانِي, شُباط, آذار — inherited from the Babylonian calendar and cousin to the Hebrew month names. Both are Modern Standard Arabic; pan-Arab news often prints both, separated by a slash. All twelve of each are on the reference sheet.

And a third Arabic option is the Japanese one: الشَّهْر السَّابِع, “the seventh month”, is ordinary speech in the Gulf and Jordan.

5.The same characters, two different words

Lesson 6's best trick was かん — the suffix that turns a point in time into a stretch of it, so なんじ asks what o'clock and なんじかん asks how many hours. The calendar is where that distinction gets sharp enough to bite, because here the two meanings share their spelling.

Both readings of both words are everyday Japanese; the kanji genuinely does not choose between them, and context does. When Japanese wants to be unambiguous it reaches for a counter instead — and the counter flips the readings back to the modern ones:

6.Dates are where the native numbers survived

Japanese has two number systems: the Chinese one you have been using (いち に さん) and an older native one (ひとつ ふたつ みっつ). The native one has been retreating for centuries. The first ten days of the month are its last stronghold.

Read the last two columns together and the list stops being ten arbitrary words: ふたつ → ふつか, みっつ → みっか. The か on the end is an old word for day in its own right.

Watch よっか against ようか — the 4th against the 8th. This is the pair learners actually confuse, and counting beats will not save you: both are three, よ・っ・か against よ・う・か. What differs is what the middle beat is — silence held in the throat for よっか, a held o for ようか. Both of those are lesson 9's small ッ and lesson 7's long vowel, met again where getting them wrong moves an appointment by four days. Say them back to back.

7.This one, last one, next one

Three prefixes cover a week, a month and a year at once — こん this, せん previous, らい coming. Nine words for the price of three, except that the year row refuses twice.

Arabic runs the same three-way split with the same economy, and it is worth learning as a set for exactly the same reason — هٰذَا this, الْمَاضِي the past one, الْقَادِم the coming one, attached to الْأُسْبُوع, الشَّهْر and السَّنَة. Unlike Japanese, Arabic makes no exception for the year.

8.Fifty-three words

The seven days, the twelve months, the dates, and the everyday words that go with them. This is the first chapter in the course whose word rule bars nothing: after lesson 9 both scripts are complete, so あさって and いっしゅうかん — which need the small っ — are finally writable.

Drill them for meaning

Three directions, as in every vocabulary chapter. Wrong answers are drawn from inside the same group, so the hard calls are the ones that are genuinely hard: よっか against ようか, しがつ against しちがつ, せんしゅう against せんげつ.

9.Ask for a date

No new grammar — the same 〜は 〜ですか。 frame from lesson 6, and its answer with the か dropped. What is new is that lesson 6 taught you three questions you had no way to answer: なんようび, なんがつ and なんにち. They have answers now.

〜は 〜ですか。

1. 1.What day of the week is it today?

   Japanese 🔊

   きょうは なんようびですか。

   kyō wa nan'yōbi desu ka

   Arabic 🔊

   أَيُّ يَوْمٍ هُوَ الْيَوْمُ؟

   ayyu yawmin huwa al-yawm

2. 2.Today is Thursday.

   Japanese 🔊

   きょうは もくようびです。

   kyō wa mokuyōbi desu

   Arabic 🔊

   الْيَوْمُ هُوَ الْخَمِيسُ.

   al-yawmu huwa al-khamīs

3. 3.What month is your birthday?

   Japanese 🔊

   たんじょうびは なんがつですか。

   tanjōbi wa nangatsu desu ka

   Arabic 🔊

   فِي أَيِّ شَهْرٍ عِيدُ مِيلَادِكَ؟

   fī ayyi shahrin ʿīdu mīlādika

4. 4.When is the holiday?

   Japanese 🔊

   やすみは いつですか。

   yasumi wa itsu desu ka

   Arabic 🔊

   مَتَى الْعُطْلَةُ؟

   matā al-ʿuṭla

5. 5.It is next Friday.

   Japanese 🔊

   らいしゅうの きんようびです。

   raishū no kin'yōbi desu

   Arabic 🔊

   يَوْمُ الْجُمُعَةِ الْقَادِمِ.

   yawmu al-jumuʿati al-qādim

Sentence 5 uses の to join one noun to another: らいしゅうの きんようび is “next week's Friday”, which is how Japanese says “next Friday”.