solitude vs surreptitiousness

solitude

noun
  • Aloneness; the state of being alone, solitary, or by oneself. 

  • A lonely or deserted place. 

surreptitiousness

noun
  • The state or quality of being surreptitious. 

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