ennui vs tiresomeness

ennui

noun
  • A gripping listlessness or melancholia caused by boredom; depression. 

verb
  • To make bored or listless; to weary. 

tiresomeness

noun
  • the state or quality of being tiresome; wearisomeness; tediousness. 

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