interstate vs main road

interstate

noun
  • A freeway that is part of the Interstate Highway System. 

adv
  • Crossing states (usually provincial state, but also e.g. multinational sense). 

adj
  • Of, or relating to two or more states. 

main road

noun
  • A major road in a town or village, or in a country area. 

  • priority road; A road with entering traffic which must yield right of way 

  • High Street; Main Street 

  • A major urban road, off which lead many smaller streets, many of them cul-de-sacs. 

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