airing vs mouthing

airing

noun
  • A public expression of an opinion or discussion of a subject. 

  • The broadcast of a television or radio show. 

  • An exposure to warm or fresh air. 

mouthing

noun
  • Ranting; passionate speech devoid of meaning. 

  • The act of forming a shape with the mouth, especially as part of sign language. 

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