From The Collaborative International Dictionary of English v.0.48 [gcide]:
Concordance \Con*cord"ance\, n. [F., fr. LL. concordantia.]
1. Agreement; accordance.
[1913 Webster]
Contrasts, and yet concordances. --Carlyle.
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2. (Gram.) Concord; agreement. [Obs.] --Aschlam.
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3. 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.
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His knowledge of the Bible was such, that he might
have been called a living concordance. --Macaulay.
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4. A topical index or orderly analysis of the contents of a
book.
[1913 Webster]
From WordNet (r) 3.0 (2006) [wn]:
concordance
n 1: a harmonious state of things in general and of their
properties (as of colors and sounds); congruity of parts
with one another and with the whole [syn: harmony,
concord, concordance]
2: agreement of opinions [syn: harmony, concord,
concordance]
3: an index of all main words in a book along with their
immediate contexts