ephemera

The ephemeron, a mayfly, lives only for a single day in its adult form.

用法提示：ephemeron 作名词，直接指代蜉蝣这种短命昆虫。

Many consider the fashion trend to be an ephemeron, destined to fade within months.

用法提示：ephemeron 作名词，比喻转瞬即逝的事物。

In literature, an ephemeron often symbolizes the fleeting nature of life.

用法提示：ephemeron 作名词，指代蜉蝣并用于象征意义。