cram school vs phrontistery

cram school

noun
  • A specialized school that trains students to meet particular goals, most commonly to pass the entrance examinations of high schools or universities. 

phrontistery

noun
  • An establishment devoted to education or study. 

  • A place for thinking. 

  • The toilet; the lavatory. 

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