万一

萬一

wànyī

conjunction/adverb HSK 4 #2,484

Meanings

Literally 'ten thousand to one' — an extremely small chance

Dài bǎ sǎn ba, wànyī xià yǔ ne.

Bring an umbrella, just in case it rains.

Wànyī tā bù lái zěnme bàn?

What if he doesn't come?

Nǐ yīnggāi duō dài xiē qián, wànyī xūyào dehuà.

You should bring extra money, just in case you need it.

usage

万一 introduces an unlikely but possible scenario. It's often followed by 怎么办 (what to do) or used at the end with 呢.

memory

Think of 万一 as 'one in ten thousand chance' — unlikely but worth preparing for.

万 wàn

一 yī