semi vs truck and trailer

semi

noun
  • A semifinal. 

  • A semi-detached house. 

  • A semi-trailer; a tractor-trailer; an eighteen-wheeler; an artic. 

  • A partial erection of the penis. 

truck and trailer

noun
  • The situation where the ball carrier leaves a maul and is followed by teammates. 

  • The situation where one player skates directly behind a teammate and holds onto their hips in order to pivot. 

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