impermanent (adj.)

• adaptable
• adjustable
• alterable
• alterative
• brittle
• capricious
• changeable
• checkered
• corruptible
• deciduous
• dying
• ephemeral
• evanescent
• ever-changing
• fading
• fickle
• fleeting
• flexible
• fluid
• fly-by-night
• flying
• fragile
• frail
• fugacious
• fugitive
• impetuous
• impulsive
• inconstant
• insubstantial
• kaleidoscopic
• malleable
• many-sided
• metamorphic
• mobile
• modifiable
• momentary
• mortal
• movable
• mutable
• nonuniform
• passing
• perishable
• permutable
• plastic
• protean
• resilient
• rubbery
• short-lived
• supple
• temporal
• temporary
• transient
• transitive
• transitory
• unstable
• variable
• volatile