nonmodern vs retro

nonmodern

adj
  • Having characteristics of past times; not modern. 

noun
  • One who is not modern. 

retro

adj
  • Of, or relating to, the past, past times, or the way things were. 

  • Affecting things past; retroactive, ex post facto. 

noun
  • Past fashions or trends. 

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