Flower in the Mirror Moon on Water in Chinese / Japanese...

鏡花水月 is an old Asian proverb that means “flowers in a mirror and the moon reflected in the lake” or “flowers reflected on a mirror and the moon reflected on the water's surface.”

Literally, 鏡花水月 reads “Mirror Flower, Water Moon.”

Figuratively this can be used to represent a lot of different ideas. It can be used to express an unrealistic rosy view or viewing things through rose-tinted spectacles. So you can use it to relay an idea about something that is visible but has no substance, something that can be seen but not touched, or something beautiful but unattainable such as dreams or a mirage.

This expression is used to describe things like the subtle and profound beauty of poems that cannot be described in words.

鏡 = Mirror (or lens)
花 = Flower(s)
水 = Water
月 = Moon

Can also be written 水月鏡花 (just a slight change in word/character order).