pixie vs trolling

pixie

noun
  • A playful sprite or elflike or fairy-like creature. 

  • A butterfly of the genus Melanis. 

  • A cute, petite woman with short hair. 

  • An upper-atmospheric optical phenomenon associated with thunderstorms, a short-lasting pinpoint of light on the surface of convective domes that produces a gnome. 

trolling

noun
  • The act of one who trolls (in various senses). 

  • A fishing technique in which one or more baited fishing lines are dragged by a moving boat. Not to be confused with trawling, which drags a net. 

How often have the words pixie and trolling occurred in a corpus of books? (source: Google Ngram Viewer )