approbative vs unctuous

approbative

noun
  • A word or grammatical form which denotes a positive affect expressing the appreciation or approval of the speaker. 

adj
  • Sanctioning officially, giving authorization or approval to something. 

  • Expressing approval. 

unctuous

adj
  • Rich, lush, intense, with layers of concentrated, soft, velvety flavor. 

  • Profusely polite, especially unpleasantly so and insincerely earnest. 

  • Oily or greasy. 

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