rematch vs semifinal

rematch

noun
  • A repeated contest staged between the same opponents or teams which played a previous contest. 

verb
  • To stage such a contest. 

  • To bring opponents together for such a contest. 

  • To match again or anew. 

semifinal

noun
  • A competition that narrows a field of contestants (semifinalists) to a set of finalists, for a subsequent final. 

  • A playoff in the round with only four players or teams left, the stage before the final. 

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