alley cat vs wild cat

alley cat

noun
  • An urban feral cat. 

  • A slut, a sexually promiscuous woman or prostitute. 

wild cat

noun
  • A feral cat. 

  • An undomesticated felid, as tigers or lions. 

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