maxilla vs mentum

maxilla

noun
  • One of the first or second pair of mouthparts posterior to the mandibles in many arthropods that are used for tasting and manipulating food. 

  • An upper jaw especially of humans and other mammals in which the bony elements are closely fused. 

  • Either of the two bones that lie with one on each side of the upper jaw lateral to the premaxilla and that in higher vertebrates bear most of the teeth. 

mentum

noun
  • A chin-like projection below the mouth of certain mollusks. 

  • The central part of the labium in insects. 

  • A projection in front of the flower in some orchids. 

  • The chin. 

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