decidedly vs obdurately

decidedly

adv
  • In a decided or final manner; resolutely. 

  • In a manner which leaves little question; definitely, clearly. 

obdurately

adv
  • In an obdurate manner; stubbornly, intractably or inflexibly. 

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