back alley vs boulevard

back alley

noun
  • An alleyway that runs behind a row of houses, or between rows of houses 

  • The anus. 

boulevard

noun
  • The landscaping on the sides of a boulevard or other thoroughfare. 

  • A broad, well-paved and landscaped thoroughfare. 

  • A strip of land between a street and sidewalk. 

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