ragging vs reprehension

ragging

noun
  • The act of one who rags or teases. 

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

reprehension

noun
  • the act, or an expression, of criticism, censure or condemnation; reprimand 

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