gabble vs mussitate

gabble

verb
  • To talk fast, idly, foolishly, or without meaning. 

  • To utter inarticulate sounds with rapidity. 

noun
  • Confused or unintelligible speech. 

mussitate

verb
  • To talk indistinctly; to mutter. 

  • To say (words, etc.) indistinctly; to mutter. 

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