Dictionary (Lat. dictio, a word), in its ordinary acceptation, a book containing the words of a language, in alphabetical order, with a definition annexed to each. The title of dictionary is also sometimes given to alphabetically arranged cyclopaedias; as dictionaries of law, of medicine, of the arts, of sciences, of commerce, etc. (See Cyclopaedia.) A complete dictionary would fulfil the same office with respect to language that a universal cyclopaedia fulfils with respect to arts, sciences, and literature, giving an account of the origin and applications of the verbal symbols of ideas and facts, as the latter gives an account of the ideas and facts themselves. It would, therefore, state the etymology of words, and note their variations in meaning through the successive periods of a literature. A glossary is a dictionary of obsolete, provincial, or technical words; and the term lexicon, though hardly distinguished by usage from dictionary, is more frequently applied to vocabularies of the ancient and learned languages, with the definitions and explanations in some modern language.

The earliest dictionary known is probably the series of clay tablets covered with cuneiform inscriptions which were found in the ruins of a palace of Nineveh, and which are ascribed to the time of the Assyrian king Asshur-bani-pal, whose seal is impressed on them. They are divided into two, and occasionally into three and even four vertical columns, in which complicated ideographic or monographic signs are explained in the more simple and phonetic syllabary of the time. Dictionaries, though not approaching the modern arrangement so closely as do these Assyrian tablets, were also in use in very ancient times among the Chinese and Japanese. The Greeks and Romans appear not to have employed dictionaries in learning foreign languages, but uniformly to have availed themselves of conversation with foreigners. Nor have any early attempts at Greek lexicography been preserved. The oldest extant Greek dictionary is by Apollonius of Alexandria, a contemporary of Augustus, whose "Homeric Lexicon" (AEElc 'OurjptKal), though much interpolated, has been of value in modern times in interpreting the idioms of the Iliad and Odyssey. Erotianus, a Greek writer in the reign of Nero, made a glossary of all the learned words found in Hippocrates. Subsequent Greek dictionaries were the Onomasticon of Julius Pollux (about A. D. 177), containing explanations of the most important words relating to various prominent subjects, the arrangement being topical instead of alphabetical; the dictionary ('Exoyn) of Attic words and phrases, by Phrynichus, an Arabian or Bithynian, who lived under Marcus Aurelius; the dictionary of the words that occur in Plato, by Timaeus the sophist, probably of the 3d century, which, though brief, contains the best explanations of terms that have come down from the ancient grammarians; a lost universal lexicon by Diogenianus of Heraclea, which is often quoted by Hesychius and Suidas, and which was abridged from an elaborate work by Pamphilus, also lost; the dictionary to the works of ten Attic orators, by Valerius Harpo-cration, of unknown date, compiled from works now lost, and of the highest importance for its explanations of legal and political terms, audits accounts of persons and things mentioned in the Attic orations; the comprehensive Greek dictionary of Hesychius, an Alexandrian grammarian of the 4th century, which, though much disfigured and interpolated in its present form, is a vast accumulation of most heterogeneous materials, and has been a principal source of our knowledge of the Greek language and of many ancient customs; the lexicon (AEEEWv Evva-yoyq) attributed to Photius, patriarch of Constantinople (died about 890); and the Greek lexicon ascribed to Suidas, of unknown date, first quoted in the 12th century, containing both common and proper names alphabetically arranged, and valuable for the literary history of antiquity, and for its citations from ancient authors, as well as for its explanation of words. - The first Roman writer on lexicography was M. Terentius Varro, the friend of Cicero; but his work, De Lingua Latina, is rather a voluminous treatise on the etymology and peculiar uses of words than a dictionary; only fragments have been preserved.

The elaborate work of Verrius Flaccus, in the earlier part of the 1st century, entitled De Significatu Verborum, is lost; but it was the basis of a valuable compilation by Pompeius Festus, in the 3d or 4th century, entitled De Significatione Verborum, which was abridged by Paulus Diaconus in the 8th century. Only one imperfect copy of the work of Festus is preserved. The words are classified alphabet!-cally according to the initial letter of each, but the order of the subsequent letters is not ob-served. The information which it contains has been of great importance on many obscure points connected with antiquities, mythology, and grammar. Near the middle of the 11th century Papias of Lombardy compiled a Latin dictionary from the glossaries of the 6th and 7th centuries. An indication of progressive learning in Italy in the 13th century was the Catholicon of Giovanni Balbi, a Genoese monk, consisting of a Latin grammar followed by a copious dictionary. The work is in Latin, forms a volume of great bulk, was written about 1280, and is now celebrated as a rare typographical curiosity, its first edition having been printed by Gutenberg in 1400. The Cornucopia of Perotti, bishop of Siponto, printed in 1489, was a copious commentary on Martial, followed by an alphabetical index of words, and was of much service to subsequent compilers.

The first edition of Calepino's Latin dictionary appeared at Reggio in 1502. At first only a Latin lexicon, additions of the corresponding Italian, Greek, German, etc, words were successively made, till it was extended (Basel, 1590-1027); to eleven languages. The French give the name calepin to any voluminous compilation. An epoch in Latin lexicography was made by the publication of Robert Stephens's Thesaurus Linguce Latinm (1532; 3d enlarged ed., 1543), which attempted to exhibit the proper use of words, not only in all the anomalies of idiom, but in every minute variation of sense. The most noted of subsequent Latin dictionaries is the Lexicon totius Latinitatis of Facciolati and Forcellini (Padua, 1771; 3d ed., 1831), in which every word is accompanied by its Italian and its Greek correlative, and which illustrates every meaning by examples from the classical authors. An English edition, edited by James Bailey, was published in London in 1828. Sir Thomas Elyot was the author of the first Latin-English dictionary (London, 1538), beyond the mere vocabularies of school boys.

He was a distinguished scholar, and a friend of Sir Thomas More; his work reached the third edition in 1545. The largest similar work that had preceded it was the Orbis Vocabulorum, printed by Wynkin de Worde in 1500 (5th ed., 1518), which by successive improvements became the popular Latin-English dictionary of Ainsworth (1736, and many subsequent editions, of which the latest is the London quarto edition edited by John Carey, LL. D.; abridgment by Thomas Morell, D. D., Philadelphia, 1863). The most eminent Latin lexicographers since Forcellini are the German scholars Scheller, Freund, and Georges. The work of Forcellini was the basis of the Latin-English dictionary of F. P. Lev-erett (Boston, 1836); and that of Freund, of the Latin-English lexicon of E. A. Andrews (New York, 1856). Many smaller lexicons have also been prepared for educational purposes, but nearly all are entirely formed from the material of the larger works. - The first modern Greek-Latin dictionary was that of Giovanni Crastoni of Piacenza (Milan, 1480; printed also by Aldus, 1497), which was for many years the only lexicographic aid for the student of Greek. Robert Constantino published at Basel, in 15(32, a thesaurus of the Greek language, in which he had the assistance of Gesner, Turnebus, Camerarius, and other learned contemporaries.

It was superseded by the Thesaurus Groecoe Linguoe of Henry Stephens (Paris, 1572), the result of 12 years' labor, which has hardly been surpassed in the comprehensive and copious interpretation of words. Its arrangement is not in the alphabetical order of words but of roots, the derivatives and compounds being collected after each root. It was the basis of the works of Scapula and Schrevelius. The most thorough subsequent Greek lexicons are the German works of Schneider, Passow, Seiler, Rost, and Pape. The work of Passow was the basis of the Greek-English lexicon of Liddell and Scott (Oxford. 1845; New York, edited by Henry Drisler, 1848; large 4to ed., London, 1870). The Greek language was long studied through the medium of the Latin, and no Greek-English lexicon was projected until the present century. The first of these that was announced was that of John Pickering (Boston, 1820, much enlarged in 1829, and subsequently in 1846), which was partially executed in 1814. It was preceded in publication only by the similar English work of John Jones (1823); that of Donnegan, an abridged translation from the German of 'Schneider, appeared in 1827. - The first standard dictionaries of modern languages were produced under the patronage of learned academies.

The oldest was the Italian Voca-bulario della Crusca, first published in 1612, which was avowedly founded on Tuscan principles, made the 14th century the Augustan period of the language, and slighted the great writers of the 16th; an enlarged edition of this work (Florence, 1729-'38) still forms the highest authority for the Italian language. In Spain the lexicon of Lebrixa (1492) and the Tesoro of Covarrubias (1611) were the only dictionaries of note till the new academy produced its great work (6 vols., Madrid, 1726-'39), an abridgment of which was immediately prepared (5th revised ed., 1817). Though German lexicography begins with Hrabanus Maurus, a contemporary of Charlemagne, the first noteworthy German lexicon was Die Teutsch Sprach of Maaler (Zurich, 1561), and the first learned and critical work of the kind was Frisch's Deutsch-lateinisches Worterbuch (Berlin, 1741). All others have been superseded successively by the work of Adelung (Leipsic, 1774-'81), and that of the brothers Grimm (Leipsic, begun in 1852.) The dictionary of the French academy was published in 1694, and adopted the alphabetical order in its 2d edition in 1718. The 6th edition was issued in 1835. A 7th edition, much improved, to be completed in 2 vols. 4to, is now (1874) in progress, and will probably be finished in 1876. M. Patin is the chief editor; MM. de Sacy, Sandeau, C. Doucet, and Mignet are associated with him.

L. N. Bescherelle's excellent dictionary of the French language, in 2 vols. 4to, appeared in 1843-'6. The large and important dictionary of M. E. Littre (3 vols. 4to, 1863-'73) is remarkably full, and has taken its place among the highest authorities. - The object of the first lexicographical labors in England was to facilitate the study of the Latin language, and bilingual dictionaries had become common while those designed for merely English readers were rare and meagre productions. Probably the earliest of the latter was that of Dr. John Bullokar, entitled "The English Ex-positour" (London, 1616), explaining, as was announced on the title page, 5,080 of what were esteemed the "hardest words;" it passed through many editions. Subsequent works were the "Glossographia, or Dictionary of Hard Words," by Thomas Blount (London, 1656); the "New World of English Words," by Edward Phillips, the nephew and pupil of Milton (1658); and the "Universal Etymological English Dictionary," by Nathan Bailey (London, 1726), in which the first attempt was made to give a complete collection of the words of the language, and which was long in the highest repute. An interleaved copy of a folio edition of Bailey's dictionary was the repository of the articles collected by Dr. Johnson in preparing his dictionary.

The work of Johnson, after eight years of arduous labor, appeared in 1755, and has exerted an influence superior to any other in fixing the external form of the language and settling the meaning of words. He first introduced into English lexicography the plan of illustrating the various significations of words by examples extracted from the best authors. It was much enlarged by Todd in the editions of 1814 and 1827, and has been the basis of many smaller works. The most important subsequent dictionaries are those of Smart, Richardson, Webster, and Worcester. Smart's dictionary, which Dr. Webster calls "most excellent," was published- in 1836, at London. Richardson's "New Dictionary of the English Language" (2 vols. 4to, London, 1835-'7) is an elaborate work, especially valuable to the student of the history of the language. Its arrangement is in the alphabetical order of the primitives, beneath each of which its derivatives are grouped. Noah Webster was engaged 36 years on his "American Dictionary of the English Language," the first edition of which was issued in 1828, in New York (2 vols. 4to), when the author was in his 70th year.

A revised edition appeared in 1840 (2. vols. 8vo), with the addition of several thousand words which in the intervening 12 years had passed from technological science into common language; and a revised appendix was added in 1843. A new edition, revised and enlarged by Prof. 0. A. Goodrich, was published in Springfield, Mass., in 1848 (1 vol. 4to, 1400 pages). In.1864 a still larger edition was published, with illustrations, after a revision of the work by Prof. Noah Porter of Yale college, who was aided by many able collaborators. For this edition much valuable matter has been added, such as a dictionary of noted names of fiction, names distinguished in modern biography, etc. Prof. James Hadley contributed to it a brief history of the English language, and an entire revision of the etymologies was made under the direction of Dr. C. A. F. Mahn of Berlin, Prussia. It forms a 4to volume of 1840 pages, containing about 114,000 words. Dr. J. E. Worcester's illustrated quarto dictionary, which had been preceded by two minor and preparatory works, was published in 1860, in Boston. This work, which contests with that of Webster the place of highest authority among American scholars, is the result of more than 30 years of labor, and contains about 104,000 words.

The chief differences between it and Webster's dictionary are found in the spelling adopted for certain classes of words. Words like centre, theatre, etc, the last syllable of which is spelled by Worcester tre, and by Webster ter, are specimens of one of the most prominent of these classes. The participles and nouns formed from verbs ending in el, etc, form a still larger class; in these Worcester doubles the l (traveller, travelling, &c), while Webster does not (traveler, traveling, &c). Other differences exist, both in methods of spelling and in definition, and to some extent in pronunciation; but for the understanding of these a thorough study of the two works is necessary. (For other dictionaries, see the articles upon the different languages.)