bull fiddle vs contrabass

bull fiddle

noun
  • A double bass (lowest-pitched of instruments of violin family). 

contrabass

noun
  • Double bass; string bass. 

  • Any of the several contrabass instruments. 

  • The person or instrument performing the contrabass part. 

  • The part or section one octave lower than bass. 

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