clandestine vs cryptozoic

clandestine

adj
  • Done or kept in secret, sometimes to conceal an illicit or improper purpose. 

  • Not recognized as a regular member. 

cryptozoic

adj
  • Hidden (especially in the soil); not easily visible. 

  • Living in a cavity or small cave. 

  • Relating to a cryptozoite. 

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