crepitate vs groan

crepitate

verb
  • to crackle, as crepitant lungs do, as some arthritic joints may do, or as some fractured bones may do. 

groan

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

  • To make a groan. 

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

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

  • A low creaking sound from applied pressure or weight. 

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