Ephemeron
例子
The rainbow was a beautiful ephemeron, disappearing as quickly as it appeared.
彩虹是一个美丽的短暂现象，消失得和出现时一样快。
The artist 's installation was designed to be an ephemeron, lasting just a few hours before it dissolved.
艺术家的装置被设计成一个短暂的存在，仅持续几个小时后就溶解了。
