accidie vs acedia

accidie

noun
  • Sloth, slothfulness, especially as inducing general listlessness and apathy. 

acedia

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

  • Spiritual or mental sloth. 

  • Boredom. 

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