coincidence vs concomitance

coincidence

noun
  • Of objects, the property of being coincident; occurring at the same time or place. 

  • A coincidence point. 

  • A fixed point of a correspondence; a point of a variety corresponding to itself under a correspondence. 

  • Of events, the appearance of a meaningful connection when there is none. 

concomitance

noun
  • occurrence or existence together or in connection with one another, coexistence 

  • A concomitant. 

  • The Roman Catholic doctrine of the existence of the entire body of Christ in the Eucharist, under each element, so that the body and blood are both received by communication in one kind only. 

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