double-faced vs shady

double-faced

adj
  • deceitful; hypocritical; treacherous 

  • Having two functional faces. 

shady

adj
  • Not trustworthy; disreputable. 

  • Abounding in shades. 

  • Mean, cruel. 

  • Overspread with shade; sheltered from the glare of light or sultry heat. 

  • Causing shade. 

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