brief brittle capricious changeable corruptible deciduous dying episodic evanescent evergreen fading fickle fleeting flitting fly-by-night flying fragile frail fugacious fugitive half-hardy hardy impermanent impetuous impulsive inconstant insubstantial momentary mortal mutable nondurable nonpermanent passing perennial perishable short short-lived subject to death temporal temporary transient transitive transitory undurable unenduring unstable volatile