intelligibility vs prattle

intelligibility

noun
  • The quality of recorded speech of every word being understandable. 

  • That which is intelligible; the degree to which something is intelligible. 

prattle

noun
  • Silly, childish talk; babble. 

verb
  • To speak incessantly and in an inconsequential or childish manner; to babble. 

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