concord vs concordance

concord

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

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

  • A state of agreement; harmony; union. 

  • 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 

concordance

noun
  • Agreement; accordance; consonance. 

  • A list of occurrences of a word or phrase from a corpus, with the immediate context. 

  • An alphabetical verbal index showing the places in the text of a book where each principal word may be found, with its immediate context in each place. 

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