foible vs inadequacy

foible

noun
  • A weakness or failing of character. 

  • A quirk, idiosyncrasy, or mannerism; an unusual habit that is slightly strange or silly. 

  • Part of a sword between the middle and the point, weaker than the forte. 

inadequacy

noun
  • A lack of competence or ability. 

  • The state of being inadequate. 

  • A shortage of required material. 

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