boff vs ha-ha

boff

noun
  • A big laugh. 

  • A great success; a hit. 

  • A pupil who works hard; a swot. 

  • A line in a film etc that elicits such a laugh. 

  • A hit or smack. 

verb
  • to have sexual intercourse (with someone) 

  • To hit; to strike. 

ha-ha

noun
  • A laugh. 

  • Something funny; a joke. 

  • A ditch with one vertical side, acting as a sunken fence, designed to block the entry of animals into lawns and parks without breaking sightlines. 

verb
  • To laugh. 

intj
  • An approximation of the sound of laughter. 

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