figure of speech vs rhetoric

figure of speech

noun
  • A word or phrase that departs from straightforward, literal language. 

rhetoric

noun
  • Meaningless language with an exaggerated style intended to impress. 

  • The art of using language, especially public speaking, as a means to persuade. 

adj
  • Synonym of rhetorical. 

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