keening vs moaning

keening

noun
  • An unpleasant wailing sound. 

  • Intense mournful wailing after a death, often at a funeral or wake 

adj
  • Sharp, shrill, especially of a sound. 

moaning

noun
  • The utterance of a moan. 

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