万が一

if by any chance, in the unlikely event that

→ 万一
adverb Rare #33,070
if by any chance, in the unlikely event that
JA: 万が一雨が降ったら、試合は中止です。
EN: If by any chance it rains, the game will be canceled.
Forms of 万一
万一万が一

もし万が一私が失敗したら両親はと言うだろう

I wonder what my parents would say if I failed.

もし万が一彼女が日本に来るとすればジェーンはとても喜ぶだろう

If by any chance she were to come to Japan, Jane would be delighted.

でもすごくゆっくり歩くからね万が一気が変わるかもしれないから

But I’ll walk very slowly, just in case you change your mind.

— 罪人たち (2025)

万が一何かあったらどうか子供たちの面倒をみてやってください

If anything should happen to me, please take care of the children.