voicing vs vowel

voicing

noun
  • A classification of speech sounds that tend to be associated with vocal cord vibration. 

  • A particular arrangement of notes to form a chord. 

  • A phonological process that turns a voiceless sound into a voiced one. 

  • The final regulation of the pitch and tone of any sound-producing entity, especially of an organ or similar musical instrument. 

  • The articulatory process in which the vocal cords vibrate. 

vowel

noun
  • A sound produced by the vocal cords with relatively little restriction of the oral cavity, forming the prominent sound of a syllable. 

  • A letter representing the sound of vowel; in English, the vowels are a, e, i, o, u, and y. 

verb
  • To add vowel points to a consonantal script (e.g. niqqud in Hebrew or harakat in Arabic). 

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