rail vs siding

rail

noun
  • A railroad; a railway, as a means of transportation. 

  • A horizontal bar extending between supports and used for support or as a barrier; a railing. 

  • A large line (portion or serving of a powdery illegal drug). 

  • A conductor maintained at a fixed electrical potential relative to ground, to which other circuit components are connected. 

  • Any of several birds in the family Rallidae. 

  • One of the lengthwise edges of a surfboard. 

  • A horizontal piece of wood that serves to separate sections of a door or window. 

  • The metal bar forming part of the track for a railroad. 

  • A vertical section on one side of a web page. 

verb
  • To enclose with rails or a railing. 

  • To range in a line. 

  • To place on a track. 

  • To sexually penetrate in a rough manner. 

  • To travel by railway. 

  • To complain violently (against, about). 

siding

noun
  • A second, relatively short length of track just to the side of a railroad track, joined to the main track by switches at one or both ends, used either for loading or unloading freight, storing trains or other rail vehicles; or to allow two trains on a same track to meet (opposite directions) or pass (same direction) (the latter sense is probably an American definition). 

  • A building material which covers and protects the sides of a house or other building. 

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