mutter vs scritch

mutter

verb
  • To make a sound with a low, rumbling noise. 

  • To speak softly and incoherently, or with imperfect articulations. 

  • To utter words, especially complaints or angry expressions, indistinctly or with a low voice and lips partly closed; to say under one's breath. 

noun
  • A repressed or obscure utterance; an instance of muttering. 

  • Peas. 

scritch

verb
  • To make a light scratching sound, like a small animal burrowing. 

  • To scratch so as to relieve an itch or irritation. 

noun
  • The act of scratching an itch. 

  • A light scratching sound, like a small animal burrowing. 

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