First opened Monday, January 29, 2007
照らす
てらす
- flat (heiban)
- 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).
to shine on, to illuminate
Terasu is originally the causative of 照る (teru, “to shine”): “to make shine”.
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 照
In a sentence
月の光が湖を照らしていた。
The moon was on the lake.
月光は水面を明るく照らした。
The moon fell brightly on the water.
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.
- “Originally the causative of 照(て)る (teru, “to shine”), from 照(て)ら (tera, the 未(み)然(ぜん)形(けい) (mizenkei, “irrealis form”) of 照(て)る (teru)) + す (-su, classical causative auxiliary, originally with 下(しも)二(に)段(だん)活(かつ)用(よう) (shimo nidan katsuyō, “lower bigrade conjugation”); modern せる (seru)), hence “to make shine”.”
Source: Wiktionary: 照らす (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.