heed vs insouciance

heed

noun
  • Careful attention. 

verb
  • To mind; to regard with care; to take notice of; to attend to; to observe. 

insouciance

noun
  • Nonchalance. 

  • Carelessness, heedlessness, indifference, or casual unconcern. 

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