Translation guide
This phrase introduces a condition that the speaker believes is very improbable. In Japanese, it is expressed through conditional forms combined with adverbs or phrases that emphasize low probability.
万一雨が降ったら
In the unlikely event that it rains
The speaker wants to say 'if this very unlikely thing happens, then...'
The most common and natural way to express 'in the unlikely event that'. 万一 (まんいち) means 'by any chance' or 'in the unlikely event'. It is used with the conditional たら form.
万一雨が降ったら、試合は中止です。
In the unlikely event that it rains, the game will be canceled.
万一彼が来なかったら、私が代わりに発表します。
In the unlikely event that he doesn't come, I'll give the presentation instead.
Similar to 万一, but slightly more emphatic about the extreme unlikelihood. Often used in formal or written contexts.
万が一事故が起きたら、すぐに連絡してください。
In the unlikely event of an accident, please contact us immediately.
Literally 'if something happens', this is a euphemistic way to refer to an unlikely or undesirable event, often used for emergencies or worst-case scenarios.
もしものことがあったら、この番号に電話してください。
In the unlikely event of an emergency, please call this number.
Used for hypothetical, often counterfactual conditions. It translates to 'even if we assume that...', emphasizing the unlikelihood.
仮に彼が辞めたとしても、プロジェクトは続けます。
In the unlikely event that he quits, we will continue the project.
Both mean 'in the unlikely event', but 万が一 is slightly more formal and emphasizes the extreme rarity of the event. 万一 is more common in everyday speech.
Avoid literal translations like 'ありそうにない出来事の場合'. They sound unnatural. Use the patterns above instead.