dog cart vs wagon

dog cart

noun
  • A two-wheeled horse-drawn carriage with two transverse seats back to back. The rear seat originally closed up to form a box for carrying dogs. 

  • A cart drawn by a dog. 

wagon

noun
  • A heavier four-wheeled (normally horse-drawn) vehicle designed to carry goods (or sometimes people). 

  • A vehicle (wagon) designed to transport goods or people on railway. 

  • A kind of prefix used in de Bruijn notation. 

  • Buttocks. 

verb
  • To load into a wagon in preparation for transportation; to transport by means of a wagon. 

  • To travel in a wagon. 

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