songbird vs sparrow

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 

sparrow

noun
  • The house sparrow, Passer domesticus; a small bird with a short bill, and brown, white and gray feathers. 

  • A member of the family Passeridae, comprising small Old World songbirds. 

  • A member of the family Emberizidae, comprising small New World songbirds. 

  • Generically, any small, nondescript bird. 

  • A quick-witted, lively person. 

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