glibness vs levity

glibness

noun
  • The condition of being glib 

levity

noun
  • The state or quality of being light, buoyancy. 

  • A lighthearted or frivolous act. 

  • Lightness of manner or speech, frivolity; lack of appropriate seriousness; inclination to make a joke of serious matters. 

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