oratorical vs vocative

oratorical

adj
  • of, or relating to oratory or an orator. 

vocative

adj
  • Used in address; appellative (said of that case or form of the noun, pronoun, or adjective, in which a person or thing is addressed). For example "Domine, O Lord" 

  • Of or pertaining to calling; used in calling or vocation. 

noun
  • The vocative case 

  • A word in the vocative case 

  • Something said to (or as though to) a particular person or thing; an entreaty, an invocation. 

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