First opened Saturday, December 9, 2006
赤い
あかい
- flat (heiban)
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).
red
Akai is from the Early Middle Japanese adjective 赤し (akashi), cognate with 明るい (akarui, “bright”).
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.
Written with 赤
In a sentence
顔が赤いよ。
Your face is red.
それの色は赤い。
Its color is red.
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.
- “From Early Middle Japanese adjective 赤(あか)し (akashi), with the 終(しゅう)止(し)形(けい) (shūshikei, “predicative form”) ending in し (shi) first replaced with the 連(れん)体(たい)形(けい) (rentaikei, “attributive form”) ending in き (ki), and then with the medial /-k-/ falling out to result in an ending of い (i). Cognate with 明るい (akarui, “bright”).”
- “Medial voiceless plosives, like /-k-/, underwent voicing, then spirantization, then gliding, then being dropped, before /-i, -u, -e, -o/. As this intervocalic sound-change did not occur before /-a/(Hamano, 2000), Middle Japanese /akaki/ became /akai/ 赤い.”
- “⟨akaki₁⟩ → */akakʲi/ → */akaɡʲi/ → */akaɣi/ → */akaji/ → */akai/.”
Source: Wiktionary: 赤い (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).
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.
- Sound change
- The pronunciation shifted over the centuries.