baseball vs rugby ball

baseball

noun
  • The ball used to play the sport of baseball. 

  • A variant of poker in which cards with baseball-related values have special significance. 

  • A sport common in North America, the Caribbean, and Japan, in which the object is to strike a ball so that one of a nine-person team can run counter-clockwise among four bases, resulting in the scoring of a run. The team with the most runs after termination of play, usually nine innings, wins. 

rugby ball

noun
  • A spheroidal ball designed for the sport of rugby. 

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