belch vs eructation

belch

noun
  • The sound one makes when belching. 

verb
  • To expel (gas) loudly from the stomach through the mouth. 

  • To eject or emit (something) with spasmodic force or noise. 

eructation

noun
  • The act of belching, of expelling gas from the stomach through the mouth. 

  • An erumpent blast of gas, wind, or other matter ejected from the depths of the earth. 

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