bikini vs swimming shorts

bikini

noun
  • A brief two-piece bathing suit worn by girls and women, especially one that exposes the midriff and navel. 

  • A brief bathing suit worn by men. 

swimming shorts

noun
  • A pair of shorts worn for swimming or bathing. 

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