evening dress vs party dress

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. 

party dress

noun
  • A woman's dress that is too elegant, revealing, dressy or impractical for normal wear. 

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