chewing vs mastication

chewing

noun
  • The act by which something is chewed on; mastication. 

  • The consumption of (the juice from) the khat plant. 

  • The consumption of loose leaf tobacco juice from tobacco plants by chewing leaves near the cheek. 

mastication

noun
  • The process of chewing. 

  • The process of crushing as though chewed. 

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