jowl vs underjaw

jowl

noun
  • the jaw, jawbone; especially one of the lateral parts of the mandible. 

  • cut of fish including the head and adjacent parts 

  • the cheek; especially the cheek meat of a hog. 

  • a fold of fatty flesh under the chin, around the cheeks, or lower jaw (as a dewlap, wattle, crop, or double chin). 

underjaw

noun
  • the lower part of the jaw 

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