bellow vs churr

bellow

noun
  • The deep roar of a large animal, or any similar loud noise. 

verb
  • To shout in a deep voice. 

  • To make a loud, deep, hollow noise like the roar of an angry bull. 

churr

noun
  • A low vocal sound made by some birds. 

verb
  • To make the low vocal sound of some birds. 

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