athenaeum vs bibliotheca

athenaeum

noun
  • An association for the advancement of learning, particularly in science or literature. 

  • A literary or scientific periodical, especially one similar to the London Athenaeum. 

  • The reading room or library of such an association; (by extension) any reading room or library. 

bibliotheca

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