hidden vs incommunicado

hidden

adj
  • Located or positioned out of sight; not visually apparent. 

  • Obscure. 

incommunicado

adj
  • In a state or condition of inability or unwillingness to communicate. 

adv
  • In a manner in which communication with outsiders is not possible, for either voluntary or involuntary reasons, especially due to confinement or reclusiveness. 

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