boak vs chunder

boak

verb
  • To retch or vomit. 

chunder

verb
  • To throw up, to vomit. 

  • Of a motor vehicle: to rumble loudly, to roar. 

noun
  • An act of vomiting. 

  • Heavy, sticky snow that makes snowsports difficult. 

  • Vomit. 

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