bebop vs instrumental

bebop

noun
  • An early form of modern jazz played by small groups and featuring driving rhythms and complex, often dissonant harmonies. 

verb
  • To participate in bebop jazz, such as by dancing in a way associated with the genre. 

  • To walk in an easygoing, carefree manner. 

instrumental

noun
  • The instrumental case. 

  • A composition written or performed without lyrics, sometimes using a lead instrument to replace vocals. 

adj
  • Pertaining to, made by, or prepared for an instrument, especially a musical instrument (rather than the human voice). 

  • Applied to a case expressing means or agency, generally indicated in English by by or with with the objective. 

  • Serving as an instrument, medium, means, or agency. 

  • essential or central; of great importance or relevance. 

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