carriage vs railroad truck

carriage

noun
  • A railroad car 

  • The part of a typewriter supporting the paper. 

  • The charge made for conveying (especially in the phrases carriage forward, when the charge is to be paid by the receiver, and carriage paid). 

  • A shopping cart. 

  • The act of conveying; carrying. 

  • A (mostly four-wheeled) lighter vehicle chiefly designed to transport people, generally drawn by horse power. 

  • Means of conveyance. 

  • A stroller; a baby carriage. 

  • The manner or posture in which one holds or positions a body part, such as one's arm or head. 

railroad truck

noun
  • A chassis or framework-like structure underneath a railroad car to which wheel axles (and, hence, wheels) are attached through bearings. (Not to be confused with railway truck or railtruck, which are British English synonyms of railroad car) 

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