dour vs forbidding

dour

adj
  • Stern, harsh and forbidding. 

  • Expressing gloom or melancholy. 

  • Unyielding and obstinate. 

forbidding

adj
  • Appearing to be threatening, unfriendly or potentially unpleasant. 

noun
  • The act by which something is forbidden; a prohibition. 

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