railroad vs underground railway

railroad

noun
  • The transportation system comprising such tracks and vehicles fitted to travel on the rails, usually with several vehicles connected together in a train. 

  • A permanent track consisting of fixed metal rails to drive trains or similar motorized vehicles on. 

  • A procedure conducted in haste without due consideration. 

  • A single, privately or publicly owned property comprising one or more such tracks and usually associated assets 

verb
  • To procedurally bully someone into an unfair agreement. 

  • To force characters to complete a task before allowing the plot to continue. 

  • To manipulate and hasten a procedure, as of formal approval of a law or resolution. 

  • To run fabric horizontally instead of the usual vertically. 

  • To travel by railroad. 

  • To engage in a hobby pertaining to railroads. 

  • To operate a railroad. 

  • To work for a railroad. 

  • To transport via railroad. 

  • To convict of a crime by circumventing due process. 

underground railway

noun
  • Synonym of subway: a railway under the ground. 

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