frou-frou vs vain

frou-frou

adj
  • Unimportant, silly, useless. 

  • Liable to create the sound of rustling cloth, similar to 19th-century dresses. 

  • Highly ornamented, overly elaborate; excessively girly. 

verb
  • To move with the sound of rustling dresses. 

noun
  • A rustling sound, particularly the rustling of a large silk dress. 

vain

adj
  • Having no real substance, value, or importance; empty; void; worthless; unsatisfying. 

  • Overly proud of oneself, especially concerning appearance; having a high opinion of one's own accomplishments with slight reason. 

  • Showy; ostentatious. 

  • Effecting no purpose; pointless, futile. 

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