[1] : The Collaborative International Dictionary of English v.0.48

evanescent \ev`anes"cent\, a. l. evanescens, -entis, p. pr. of
   evanescere.
   1. liable to vanish or pass away like vapor; vanishing;
      fleeting; as, evanescent joys.
      1913 webster

            so evanescent are the fashions of the world in these
            particulars.                          --hawthorne.
      1913 webster

   2. vanishing from notice; imperceptible.
      1913 webster

            the difference between right and wrong, in some
            petty cases, is almost evanescent.    --wollaston.
      1913 webster

[2] : WordNet (r) 2.0

evanescent
     adj : tending to vanish like vapor; "evanescent beauty"

[3] : Moby Thesaurus II by Grady Ward, 1.0

65 moby thesaurus words for "evanescent":
   atomic, brittle, capricious, changeable, corpuscular, corruptible,
   deciduous, disappearing, dissolving, dying, embryonic, ephemeral,
   evaporating, fading, fickle, fleeting, flitting, 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, nondurable,
   nonpermanent, passing, perishable, short-lived, subatomic,
   temporal, temporary, tenuous, thin, transient, transitive,
   transitory, ultramicroscopic, undurable, unenduring, unseeable,
   unstable, vanishing, volatile

Evanescent >> E Words
Evanescent, definition of term: Evanescent
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