apropos vs to

apropos

prep
  • Regarding or concerning. 

adj
  • Of an appropriate or pertinent nature. 

  • by the way, incidental 

adv
  • To the purpose; appropriately. 

  • By the way. 

  • Timely; at a good time. 

to

prep
  • according to 

  • Used to indicate the target or recipient of an action. 

  • Used to indicate result of action. 

  • Used to indicate a ratio or comparison; compared to, as against. 

  • Used to indicate that the preceding term is to be raised to the power of the following value; indicates exponentiation. 

  • At. 

  • Used after an adjective to indicate its application. 

  • Preceding the next hour. 

  • Indicating destination: In the direction of, so as to arrive at. 

  • Denotes the end of a range. 

  • Often used without the hour 

  • Used to describe what something consists of or contains. 

  • Used to indicate a resulting feeling or emotion. 

particle
  • Used to indicate an obligation on the part of, or a directive given to, the subject. 

  • In order to. 

  • As above, with the verb implied. 

  • A particle used for marking the following verb as an infinitive. 

adv
  • Toward a closed, touching or engaging position. 

  • Into the wind. 

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