approximal vs vincinal

approximal

adj
  • Near or adjacent 

  • Contiguous 

vincinal

adj
  • Of, belonging to, or restricted to a limited area or neighborhood; local. 

  • Relating to or being a local road. 

  • Mineralogy. Approximating, resembling, or taking the place of a fundamental crystalline form or face. 

  • Chemistry. Of or relating to the consecutive positions of substituted elements or radicals on an organic compound. 

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