dusky vs pitch-dark

dusky

adj
  • Having a shade of color that is rather dark. 

  • Ashen; having a greyish skin coloration. 

  • Dimly lit, as at dusk (evening). 

noun
  • A dusky dolphin. 

  • A dusky grouse. 

  • A dusky shark. 

pitch-dark

adj
  • Absolutely dark or black; as dark as pitch. 

How often have the words dusky and pitch-dark occurred in a corpus of books? (source: Google Ngram Viewer )