万に一つ

• 読み: まんにひとつ
• ローマ字: man ni hitotsu
• 漢字の分解: 万 (man) — ten thousand; 一 (ichi/hito) — one
• 発音: /maɴ.ni.çi.to.tsɯ/

意味

One in ten thousand; one in a million; in the unlikely event. Describes an extremely slim chance.

An expression functioning as an adverb or attributive adjective (with の). Used to describe an extremely unlikely possibility: 万に一つの可能性 (one-in-a-million chance). Often appears in conditional patterns: 万に一つでも (even if there's the slightest chance). Despite emphasising low probability, it is frequently used when that slim chance still matters and must be prepared for.

例文

1. 万に一つの確率でも、備えておくべきだ。
2. 成功する見込みは万に一つもないと思われていた。
3. 万に一つのことがあったら困るので保険に入った。

使い方ガイド

場面: risk assessment, insurance, cautionary talk

トーン: cautionary

起源と歴史

From 万 (man, ten thousand) + に (ni, in/among) + 一つ (hitotsu, one). Literally 'one in ten thousand' — expressing the rarest of occurrences.

文化的背景

時代: Classical origin

世代: All ages

社会的背景: Universal