万一

まんいち · manichi · JLPT N3 · noun

probability

🎲 万一 = ten thousand + one: a one-in-ten-thousand chance

万 means ten thousand and 一 means one, so 万一 is literally one out of ten thousand: a slim chance. Say it before a possibility you don't expect but want to cover, as in 万一雨が降ったら (if by any chance it rains).

万 — top 一 + 𠃌 (hook) over 丿
Originally a pictograph of a scorpion, used in oracle bone script. It was borrowed phonetically to mean 'ten thousand' and the original scorpion sense was lost. The traditional form 萬 shows the scorpion more clearly; 万 is a simplified variant long used as a common shorthand.

一 — single horizontal stroke
一 is one of the simplest pictographs in Chinese, depicting a single horizontal line to represent the number one. It has retained essentially the same form since oracle bone script over 3,000 years ago. By extension it also means 'first,' 'whole,' or 'same.'

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