fearful vs vacillant

fearful

adj

  • Frightening; causing fear. 

  • Tending to fear; timid. 

adv

  • Extremely; fearfully. 

vacillant

adj

  • Vacillating; wavering; fluctuating; irresolute. 

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