First opened Tuesday, June 15, 2010
昨日
きのう
- middle-high (nakadaka): falls after mora 2
How to read it: a line over a kana means the voice is high there, and ↓ marks where it drops. A kana with no line is low. With no ↓ the pitch stays high to the end and does not drop even on a following particle (が, は).
yesterday
Kinō went kinopu → kinoɸu → kinowu → kinou → kinoː, and its initial ki is unclear.
Taken apart
No breakdown is shown for this word: Wiktionary's text for it doesn't give a split that spells the word and joins to its reading, and any other split would be a guess.
In a sentence
きのう雨が降った。
It rained yesterday.
きのう魚を３匹捕った。
I caught three fish yesterday.
Sentences are from Tatoeba (CC BY 2.0 FR), picked by fixed rules from a dated export and shown unchanged. Nobody has reviewed them one by one.
What Wiktionary says
Quoted line by line from Wiktionary's Etymology section for this reading, taken from one dated dump so it can't change underneath us. Nothing below is paraphrased.
Not settled
Wiktionary itself hedges on part of this word's origin — those lines are marked below.
- “/ki no pu/ → /kinoɸu/ → */kinowu/ → /kinou/ → /kinoː/”
- “From Old Japanese, ultimately from Proto-Japonic *kinəpu.”
- Hedged“The initial ki is unclear, but is likely the same ki element that appears in other words pertaining to the past. This may be related to the now-obsolete auxiliary verb き (ki) indicating the recollective past -- see けり (keri). The middle no appears to be the regular genitive particle の (no). The final pu is an apophonic form of 日 (hi, “day”), also found in 今日 (kepu→kyō, “today”).”
- Hedged“Martin suggests that the initial ki might also be related to Old Japanese 來 (ku, “to come”), modern 来る (kuru), presumably via the 連用形 (ren'yōkei, “continuative or stem form”) of ki. However, this is problematic both semantically, as "the coming day" would presumably refer to tomorrow rather than yesterday; and grammatically, as a verb modifying a noun would be expected to conjugate into the regular attributive form (for 來 (ku) that would be kuru), rather than into the continuative form that then necessitates a particle.”
- “The kanji are orthographic borrowing from Chinese 昨日 (zuórì).”
Source: Wiktionary: 昨日 (dump of 2026-09-02), available under CC BY-SA 4.0. Reading, meaning and part of speech from JMdict, and kanji readings from KANJIDIC2 (EDRDG).
Other readings of 昨日 on the same Wiktionary page
These describe other words written the same way, not きのう. They are quoted for context: the parts, layer and processes of this word are not taken from them.
さくじつ
- “From Middle Chinese compound 昨日 (dzak nyit, literally “yesterday + day”). Compare modern Cantonese reading zok⁶ jat⁶.”
きそ
- “From Old Japanese. The initial ki is unclear, but is likely the same ki element that appears in other words pertaining to the past. This may be related to the now-obsolete auxiliary verb き (ki) indicating the recollective past -- see けり (keri). The final so is also unclear, but is probably the same as the final zo in 去年(こぞ) (kozo).”
- “This may have been read as kizo in Old Japanese.”
What the labels mean
- 和語 Native Japanese
- Words that were already Japanese before Chinese vocabulary arrived — usually written with kun'yomi and often short.
- Borrowing
- Taken over from another language.
- Sound change
- The pronunciation shifted over the centuries.
- Ateji
- Kanji chosen for their sound or sense after the word existed.
- Origin unclear
- Scholars disagree, or nobody knows.