Translation guide
A device or substance that triggers an explosion. In Japanese, the term depends on whether you mean a mechanical/electrical device, a blasting cap, or a chemical initiator.
A mechanical or electrical device used to trigger an explosion, such as in mining, demolition, or military contexts.
General term for a detonating device; literally 'initiating explosion device'. Used in technical and formal contexts.
爆弾の起爆装置が作動した。
The bomb's detonator activated.
Fuze or detonator, often for military ordnance like shells or bombs. Can refer to the entire fuze mechanism.
砲弾の信管が外れていた。
The shell's fuze was detached.
Blasting cap; a small sensitive explosive used to set off a larger charge. Common in mining and construction.
雷管をダイナマイトに差し込んだ。
He inserted the blasting cap into the dynamite.
A sensitive chemical compound used to trigger a larger explosive reaction, such as lead azide or mercury fulminate.
Initiating explosive; the chemical substance that detonates first. Used in chemistry and pyrotechnics.
起爆薬としてアジ化鉛が使われる。
Lead azide is used as a detonator (initiating explosive).
A person, event, or thing that sets off a sudden, often violent, chain of events.
Literally 'trigger' (of a gun). Figuratively, the catalyst or immediate cause of an event. Very common in news and conversation.
その発言が暴動の引き金になった。
That remark was the detonator for the riot.
Literally 'a spark' or 'ember'. Figuratively, the root cause or trigger of trouble or conflict.
起爆装置 is the broadest term for any detonating device. 信管 is specifically a fuze for military ordnance. 雷管 is a blasting cap used with commercial explosives. Use 起爆装置 when unsure.
In figurative contexts, do not use 起爆装置. Instead, use 引き金 (trigger) or 火種 (spark). Saying 事件の起爆装置 sounds unnatural.
A small misunderstanding became the detonator for a big fight.