deverbal vs viva voce

deverbal

adj

  • Derived from a verb. 

noun

  • A word, especially a substantive, that is derived from a verb. 

viva voce

adj

  • By word of mouth. 

adv

  • By word of mouth. 

noun

  • An oral examination. 

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