something illusory, ephemeral, or unreal; a beautiful but insubstantial vision or illusion, like the moon reflected in water or an image in a mirror.
他所追求的那些浮华名利，最终不过是水月镜像，一场空欢喜。
The superficial fame and fortune he pursued were ultimately nothing more than an illusory image, a joy that came to nothing.
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