ballroom vs coliseum

ballroom

noun
  • A large room used for dancing and banquets. 

  • A type of elegant dance. 

verb
  • To take part in ballroom dancing. 

coliseum

noun
  • A large theatre, cinema, or stadium. 

  • A large, often circular building, for indoor sporting events, exhibitions, concerts, etc.; arena. 

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