nebulous vs vaporific

nebulous

adj
  • In the form of a cloud or haze; hazy. 

  • Vague or ill-defined. 

  • Relating to a nebula or nebulae. 

vaporific

adj
  • Producing vapour; tending to pass, or to cause to pass, into vapor. 

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