atypical vs quicksilver

atypical

adj
  • Unusual or irregular. 

  • Not conforming to the normal type. 

noun
  • An atypical antipsychotic. 

quicksilver

adj
  • Unpredictable, erratic or fickle; mercurial. 

noun
  • The metal mercury. 

  • An amalgam of mercury and tin applied to the backs of mirrors, quicksilvering. 

verb
  • To overlay with quicksilver. 

  • To treat with quicksilver. 

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