Transience

n.

1.

The quality of being transient; transientness.

Noun	1.	transience - an impermanence that suggests the inevitability of ending or dying Synonyms: transiency, transitoriness
	2.	transience - the attribute of being brief or fleeting Synonyms: brevity, briefness

ephemerality, ephemeralness, fleetingness, fugaciousness, fugacity, impermanence, impermanency, transiency, transitoriness