nonpermanent (?.)
- brittle
- capricious
- changeable
- corruptible
- deciduous
- dying
- ephemeral
- evanescent
- fading
- fickle
- fleeting
- flitting
- fly-by-night
- flying
- fragile
- frail
- fugacious
- fugitive
- impermanent
- impetuous
- impulsive
- inconstant
- insubstantial
- momentary
- mortal
- mutable
- nondurable
- passing
- perishable
- short-lived
- temporal
- temporary
- transient
- transitive
- transitory
- undurable
- unenduring
- unstable
- volatile