churr vs groan

churr

noun
  • A low vocal sound made by some birds. 

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

groan

noun
  • A low creaking sound from applied pressure or weight. 

  • A low, mournful sound uttered in pain or grief. 

  • A low, guttural sound uttered in frustration, disapproval, or ecstasy. 

verb
  • To seemingly creak under the strain of being heavily laden. 

  • To make a groan. 

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