cantor vs songbird

cantor

noun
  • singer, especially someone who takes a special role of singing or song leading at a ceremony 

  • A prayer leader in a Jewish service; a hazzan 

songbird

noun
  • A bird having a melodious song or call. 

  • Any bird in the passerine suborder Passeri, which are distinguished by a more sophisticated vocal apparatus 

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