notice vs secret

notice

verb
  • To be noticeable; to show. 

  • To become aware of; to observe. 

noun
  • A published critical review of a play or the like. 

  • A written or printed announcement. 

  • Advance notification of termination of employment, given by an employer to an employee or vice versa. 

  • The act of observing; perception. 

  • A formal notification or warning. 

  • Prior notification. 

secret

verb
  • To make or keep secret. 

  • To hide secretly. 

noun
  • Private seclusion. 

  • A piece of knowledge that is hidden and intended to be kept hidden. 

  • The key or principle by which something is made clear; the knack. 

  • A form of steel skullcap. 

  • Something not understood or known. 

  • Any prayer spoken inaudibly and not aloud; especially, one of the prayers in the Tridentine Mass, immediately following the "orate, fratres", said inaudibly by the celebrant. 

adj
  • Being or kept hidden. 

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