freighter vs wheels

freighter

noun
  • One for whom freight is transported. 

  • One employed in receiving and forwarding freight. 

  • An aircraft used mainly to carry freight; a cargo aircraft or cargo plane. 

  • A vessel used mainly to carry freight; a cargo ship. 

  • One who loads a ship, or one who charters and loads a ship. 

wheels

noun
  • An automobile or other vehicle; a set of wheels. 

  • Well-developed thigh muscles. 

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