evanescence.

Evanescence (n) comes from the Latin evanescere meaning "disappear, vanish." Something that possesses qualities of evanescence, has a quality of disappearing or vanishing. The evanescence of a shooting star makes it hard to catch - it's there one moment and gone the next. Evanescence is a word typically used to describe an event that fades from sight or memory, or sometimes the fleeting quality of worldly success. (©®vocabulary.com)