evanescent (adj.)
- atomic
- brittle
- capricious
- changeable
- corpuscular
- corruptible
- deciduous
- dying
- embryonic
- ephemeral
- fading
- fickle
- fleeting
- fly-by-night
- flying
- fragile
- frail
- fugacious
- fugitive
- germinal
- granular
- impalpable
- imperceptible
- impermanent
- impetuous
- imponderable
- impulsive
- inappreciable
- inconstant
- indiscernible
- infinitesimal
- insubstantial
- intangible
- invisible
- melting
- microcosmic
- microscopic
- molecular
- momentary
- mortal
- mutable
- passing
- perishable
- short-lived
- subatomic
- temporal
- temporary
- tenuous
- thin
- transient
- transitive
- transitory
- ultramicroscopic
- unseeable
- unstable
- volatile
