banker vs trackbed

banker

noun
  • A railway locomotive that can be attached to the rear of a train to assist it in climbing an incline. 

  • A ditcher; a drain digger. 

  • A banksman. 

  • The dealer in a casino, or one who keeps the bank in a banking game. 

  • A vessel employed in the cod fishery on the banks of Newfoundland. 

  • One who conducts the business of banking; one who, individually, or as a member of a company, keeps an establishment for the deposit or loan of money, or for traffic in money, bills of exchange, etc. 

  • The stone bench on which a mason cuts or squares his work. 

trackbed

noun
  • The layer of gravel or other foundation on which a railway track is laid. 

  • The land on which a railway (especially one that has been closed or dismantled) was built; the roadbed for a railroad. 

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