dumb vs voiceless

dumb

adj
  • Pointless, foolish, lacking intellectual content or value. 

  • Lacking brightness or clearness, as a colour. 

  • Extremely stupid. 

verb
  • To make stupid. 

  • To represent as stupid. 

  • To reduce the intellectual demands of. 

voiceless

adj
  • Lacking a voice, without vocal sound. 

  • Spoken without vibration of the vocal cords; unvoiced, surd, breathed. Examples: [t], [s], [f], [m̥], [u̥]. 

  • Without a vote; having no input into a decision. 

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