bad apple vs vile

bad apple

noun
  • A person who is not wholesome, honest, or trustworthy, especially one who has an adverse influence on others. 

vile

adj
  • Morally low; base; despicable. 

  • Causing physical or mental repulsion; horrid. 

How often have the words bad apple and vile occurred in a corpus of books? (source: Google Ngram Viewer )