apropos vs past

apropos

adj
  • by the way, incidental 

  • Of an appropriate or pertinent nature. 

adv
  • To the purpose; appropriately. 

  • By the way. 

  • Timely; at a good time. 

prep
  • Regarding or concerning. 

past

adj
  • Having already happened; in the past; finished. 

  • Of a period of time: having just gone by; previous. 

  • Following expressions of time to indicate how long ago something happened; ago. 

  • Of a tense, expressing action that has already happened or a previously-existing state. 

prep
  • Beyond in place or quantity 

  • Any number of minutes after the last hour 

  • Having recovered or moved on from (a traumatic experience, etc.). 

  • No longer capable of. 

  • Passing by, especially without stopping or being delayed. 

adv
  • In a direction that passes. 

noun
  • The period of time that has already happened, in contrast to the present and the future. 

  • The past tense. 

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