antipodal vs diametrical

antipodal

adj
  • diametrically opposite 

  • On opposite sides of the globe; pertaining to antipodes 

noun
  • One of the cells at the chalazal pole of an embryo sac. 

diametrical

adj
  • Of or pertaining to a diagonal or diameter 

  • Completely opposed 

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