concord vs concurrence

concord

noun
  • A state of agreement; harmony; union. 

  • Agreement of words with one another, in gender, number, person or case. 

  • An agreeable combination of tones simultaneously heard; a consonant chord; consonance; harmony. 

  • A variety of sweet American grape, with large dark blue (almost black) grapes in compact clusters; a Concord grape. 

verb
  • To agree; to act together 

concurrence

noun
  • Agreement; concurring. 

  • An instance of simultaneous occurrence. 

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