Evanescent \Ev`a*nes"cent\, a. [L. evanescens, -entis, p. pr. of
   evanescere.]
   1. Liable to vanish or pass away like vapor; vanishing;
      fleeting; as, evanescent joys.
      
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            So evanescent are the fashions of the world in these
            particulars.                          --Hawthorne.
      
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   2. Vanishing from notice; imperceptible.
      
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            The difference between right and wrong, in some
            petty cases, is almost evanescent.    --Wollaston.
      
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