persiflage vs ragging

persiflage

noun
  • Frivolous, lighthearted discussion of a topic. 

  • Good-natured banter; raillery. 

ragging

noun
  • The act of one who rags or teases. 

  • An initiation in educational institutions (e.g. universities) usually involving harassment by upperclassmen. 

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