惊鸿照影
[jīng hóng zhào yĭng]
'惊鸿照影' (jing hong zhao ying) evokes an image of fleeting beauty. Historically, it is used to describe an exceptionally beautiful woman seen briefly, like the reflection of a graceful swan as it flies by. The impression left is unforgettable though brief, similar to the sudden appearance of a startled swan reflecting in water before disappearing again.