maw vs midriff

maw

noun
  • The upper digestive tract (where food enters the body), especially the mouth and jaws of a fearsome and ravenous creature. 

  • Mother. 

  • Any large, insatiable or perilous opening. 

  • Appetite; inclination. 

  • The mouth. 

  • A gull. 

midriff

noun
  • The middle section of the human torso, from below the chest to above the waist 

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