timidity vs trepidation

timidity

noun
  • The state of being timid; shyness. 

trepidation

noun
  • A fearful state; a state of concern or hesitation. 

  • An involuntary trembling, sometimes an effect of paralysis, but usually caused by terror or fear. 

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