evening dress vs toga

evening dress

noun
  • An elegant dress worn by women, especially for social events in the evening, an evening gown. 

  • formal attire worn for evening social events. 

toga

noun
  • A loose wrap gown. 

  • An academic gown. 

  • A loose outer garment worn by the citizens of Ancient Rome. 

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