Concordance
2 of the 7 encyclopedias on this shelf carry an entry for Concordance. Both are reproduced below, so you can see where they agree and where they differ.
Collier's New Encyclopedia (1921)
a book of reference in which all the words existing in a particular version of the Bible are arranged alphabetically - part of the verse being extracted with each, so that if one remember a notable word in any part of the Bible he may find, with scarcely any expenditure of time, where it occurs. A similar work may be constructed to enable students to find where each Hebrew word occurs in the Old Testament, or each Greek one in the New Testament or in the Septuagint. The first known Concordance of the Bible in any language was that of St. Anthony of Padua, who was born in 1195, and died in 1231. His work was called "Concordantiæ Morales," and was of the Morales, Latin Vulgate. The first Hebrew Concordance was that of Rabbi Isaac Nathan, commenced in 1438 and finished in 1448. The first Greek Concordance to the New Testament was that of Xystus Betuleius, whose real name was Birck; it came forth in A. D. 1546. The first English Concordance to the New Testament was that of Thomas Gybson, before A. D. 1540; the first to the whole English version of the Bible that of Marbeck, A. D. 1550. These, of course, preceded the appearance in A. D. 1611 of the authorized version of the Bible. The elaborate and well-known work of Cruden appeared first in 1737. The first known Concordance to Shakespeare was that of Ayscough, in 1790. Mrs. Cowden Clarke's elaborate and most useful work first appeared in 1847. Concordances to Milton, Thompson, and other celebrated poets and authors have been published.
Aiton's Encyclopedia (1910)
a finding list of passages in an important work or series of writings. The principal words are arranged alphabetically. Under each, the various phrases are cited in which the word occurs. Perhaps the most celebrated is the concordance to the Holy Scriptures by Alexander Cruden, published in 1737. If we want to find an account of the destruction of the temple by Samson, we turn to posts and find the following: Judges xvi: 3, Samson took the two p. Turning to the third verse of the sixteenth chapter of Judges, we find the desired passage. Numerous concordances to Shakespeare's works have appeared. The best is that by John Bartlett, published in New York in 1894. The alphabetical index placed usually at the end of an author's work, is a brief concordance.