paroxysmal vs tremulous

paroxysmal

adj
  • Of, pertaining to, causing or accompanied by paroxysms. 

tremulous

adj
  • Trembling, quivering, or shaking. 

  • Timid, hesitant; lacking confidence. 

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