不翼而飞

bù yì ér fēi

to vanish into thin air

Character by character

不bù
no

翼yì
wings

而ér
yet

飞fēi
fly

我放在桌上的钱包不翼而飞了。

The wallet I left on the table has vanished.

Tone: neutral.

From Guanzi, where 'what flies without wings' was the human voice; now things that mysteriously disappear.

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