cud vs mastication

cud

noun
  • The portion of food which is brought back into the mouth by ruminating animals from their first stomach, to be chewed a second time. 

verb
  • To bring back into the mouth and chew a second time. 

mastication

noun
  • The process of chewing. 

  • The process of crushing as though chewed. 

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