fumfer vs mussitate

fumfer

verb
  • To mumble, to mutter, to murmur. 

  • To dither, to waffle. 

  • To be evasive, to temporize, to stall. 

  • To putter aimlessly. 

mussitate

verb
  • To talk indistinctly; to mutter. 

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

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