Translation guide
A sudden loud crash of thunder, or a metaphorical shock.
Describing the sound of thunder itself, especially a single loud burst.
The most direct and common word for a thunderclap or peal of thunder. Used in both spoken and written Japanese.
Using 'thunderclap' metaphorically to describe something startling or unexpected.
A common idiom meaning 'a bolt from the blue' or 'a complete surprise'. Perfect for a sudden, shocking event.
彼の辞任は青天の霹靂だった。
His resignation was a thunderclap out of the blue.
雷 (かみなり) is the general term for thunder and lightning. 雷鳴 (らいめい) specifically refers to the rumbling or clapping sound of thunder. Use 雷鳴 when you want to emphasize the auditory aspect of a thunderclap.
For the figurative sense, 青天の霹靂 (せいてんのへきれき) is the closest equivalent to 'thunderclap' as a sudden shock. 寝耳に水 (ねみみにみず) is also common but slightly more informal.
突然、大きな雷鳴がとどろいた。
Suddenly, a loud thunderclap roared.
Literally 'thunder falls', this phrase describes a lightning strike and the accompanying thunderclap. Often used for a nearby strike.
近くに雷が落ちて、すごい音がした。
Lightning struck nearby with a tremendous thunderclap.
The general word for thunder or lightning. In context, it can refer to a thunderclap, but it's broader than 雷鳴.
Can mean both thunder and lightning. Use 雷鳴 for a specific loud clap.
雷がゴロゴロ鳴っている。
Thunder is rumbling. (Not a single clap, but continuous thunder.)
Literally 'sound of thunder'. A descriptive phrase, less common as a single term.
雷の音で目が覚めた。
I woke up to the sound of thunder.
Another idiom for a sudden shock or surprise, literally 'water in a sleeping ear'. Slightly more colloquial than 青天の霹靂.
その知らせは寝耳に水だった。
The news hit me like a thunderclap.
Means 'shock' or 'impact'. Can be used for a thunderclap-like shock, but lacks the suddenness nuance.
その発表は大きな衝撃を与えた。
The announcement came as a thunderclap.