pungent vs vacuous

pungent

adj
  • Stinging; acerbic. 

  • Having a sharp and stiff point. 

  • Having a strong odor that stings the nose, said especially of acidic or spicy substances. 

  • Having a strong taste that stings the tongue, said especially of hot (spicy) food, which has a strong and sharp or bitter taste. 

vacuous

adj
  • Showing a lack of thought or intelligence; vacant. 

  • Empty; void; lacking meaningful content. 

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