acedia vs boredom

acedia

noun
  • Boredom. 

  • Apathy; a lack of care or interest; indifference. 

  • Spiritual or mental sloth. 

boredom

noun
  • The state of being bored. 

  • An instance or period of being bored; A bored state. 

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