alliteration vs proteron

alliteration

noun
  • The recurrence of the same letter in accented parts of words, as in Anglo-Saxon alliterative meter. 

  • The repetition of consonant sounds at the beginning of two or more words immediately succeeding each other, or at short intervals. 

proteron

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