mandible vs pharynx

mandible

noun
  • One of the anterior pair of mouthparts of an arthropod, designed for holding and cutting food. 

  • Any of various invertebrate mouthparts serving to hold or bite food materials. 

  • The jaw or a jawbone, especially the lower jawbone in mammals and fishes. 

  • Either of the upper and lower segments of a bird's beak. 

pharynx

noun
  • The part of the alimentary canal immediately behind the mouth in invertebrates that may be thickened and muscular, eversible and toothed, or adapted as a suctorial organ. 

  • The part of the alimentary canal and respiratory tract that extends from the back of the mouth and nasal cavity to the larynx and esophagus. 

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