boff vs yak

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. 

yak

noun
  • A laugh. 

  • An ox-like mammal native to the Himalayas, Mongolia, Burma, and Tibet with dark, long, and silky hair, a horse-like tail, and a full, bushy mane. 

  • A talk, particular an informal talk; chattering; gossip. 

  • Vomit. 

  • A kayak. 

verb
  • To talk, particularly informally but persistently; to chatter or prattle. 

  • To vomit, usually as a result of excessive alcohol consumption. 

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