roadster vs winter rat

roadster

noun
  • An open automobile having a front seat and a rumble seat. 

  • A person who lives along the road. 

  • a sea-going vessel riding at anchor in a road or bay. 

  • A clumsy vessel that works its way from one anchorage to another by means of the tides. 

  • A bicycle, or tricycle, adapted for common roads, rather than for the racing track, usually of classic style and steel-framed construction. 

winter rat

noun
  • An old, unattractive automobile, purchased for little money, to be driven during brutal Great Lakes winters while the owner's "good" car remains garaged and protected from corrosive road salt for the season. 

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