chortle vs haha

chortle

verb
  • To laugh with a chortle or chortles. 

noun
  • A similar sounding vocalisation of various birds. 

  • A joyful, somewhat muffled laugh, rather like a snorting chuckle. 

haha

verb
  • To laugh. 

noun
  • Type of boundary to a garden, pleasure-ground, or park, designed not to interrupt the view and to be invisible until closely approached. 

  • A large leafy Hawaiian plant, Gunnera petaloidea. 

intj
  • An onomatopoeic representation of laughter. 

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