idling vs vapid

idling

noun
  • An idle period; something done idly. 

vapid

adj
  • Lifeless, dull, or banal. 

  • Offering nothing that is stimulating or challenging. 

  • Tasteless, bland, or insipid. 

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