bullheaded vs flexible

bullheaded

adj
  • unreasonably stubborn. 

flexible

adj
  • Willing or prone to give way to the influence of others; not invincibly rigid or obstinate. 

  • Capable or being adapted or molded in some way. 

  • Capable of being flexed or bent without breaking; able to be turned or twisted without breaking. 

noun
  • Something that is flexible. 

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