adj.
  - chiefly literary quickly fading from sight, memory, or existence.
- Physics  denoting a field or wave which extends into a region where it cannot propagate and whose amplitude therefore decreases with distance.
Derivative
  
    - evanesce v.
- evanescence n.
- evanescently adv.
 
  Etymology
  C18: from L. evanescent-, evanescere ‘disappear’.