Transience (noun)

The quality or condition of being transient; impermanence.

Origin:

Late 16th century: from french transience or latin transientia, from transire "to pass over".

Examples:

1. The transience of youth was a poignant reminder that time was fleeting.
2. The transience of life was a common theme in the artist's work.
3. The transience of fame was something the celebrity was well aware of.
4. The transience of beauty was a bitter lesson the model had learned early in her career.
5. The transience of happiness was a concept that the philosopher struggled with in his writings.