concealment vs secrecy

concealment

noun
  • The practice of keeping secrets. 

  • protection from observation or surveillance. 

  • The condition of being hidden or concealed. 

secrecy

noun
  • The habit of keeping secrets. 

  • Concealment; the condition of being secret or hidden. 

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