apprehensive vs incredulous

apprehensive

adj
  • Anticipating something with anxiety, fear, or doubt; reluctant. 

incredulous

adj
  • Skeptical, disbelieving, or unable to believe. 

  • Difficult to believe; incredible. 

  • Expressing or indicative of incredulity. 

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