Dictionaries of the English language will be necessary for many people for the foreseeable future. They are indispensable in a family, especially one in which children are growing up, in many professional offices, in schools, in reference facilities, and in many other circumstances. But, if you go to a bookstore, what should you look for?
What is the role of dictionaries? First, they are a guide to how we think about the world. This is the area of definitions. There may be many meanings of a word, or many fixed phrases of which it is part, or it may have a single specific sense which is identical all over the world wherever English is spoken. In the dictionary entry, the definitions may be arranged in sequence corresponding to the frequency of occurrence of a particular meaning in the language in modern times, with the most common meaning first, or in order of the historical development of the word's use in the language, with the earliest recorded meaning first and then the successive meanings as meaning changed. Examples of the use of a word and literary quotations may be absent or abundant, and the type of formal or informal, written or spoken language that serves as the base for a dictionary may vary. Irregular forms and alternative formations should be listed for each word.
We may want information about the history of a word, which is a linguist's definition of etymology. Some dictionaries emphasize the history of the elements of the word (root-etymology), while others emphasize the development of its form and use, and borrowing. Many English words are borrowed from French, Latin, Greek, or other European languages, with a smaller native group stemming from the Anglo-Saxon (early Germanic) and Celtic languages spoken by the inhabitants of Britain at the time of the Norman invasion (1066 AD) which preceded the creation of modern English.
To the extent that dictionaries include encyclopedic material, they may contain much information about such fields as history, geography, and science. However, encyclopedic information may age rapidly, since the population of Upper Volta, for instance, changes over the years. Although encyclopedic material is useful, this effect may date a dictionary while its basic lexical material is still valuable.
Dictionaries may be relied on for information about correct pronunciation of English, which of course differs in different parts of the world, so that several different pronunciations may be offered and may need to be discriminated. For many people, dictionaries are a guide to the usage of a foreign language (English) which the user may not be able to pronounce or use correctly, or they may help a speaker of a non-standard dialect of English to learn how a word should be pronounced in some form of standard English.
We want our dictionary to contain many different words. The unabridged English dictionaries, such as you might find on a good library reference shelf, include a quarter of a million to half a million entries. This discussion will focus on the unabridged dictionaries of English, and the shorter dictionaries based on them or constructed on comparable principles so that they have reference value.
The first lines of design of our modern English dictionaries came from a scholarly English archbishop, Richard Trench (1807-1886), who recommended in 1857 in papers presented to the Philological Society that the material in entries in dictionaries should be chronologically arranged and based on collections of citations from texts. Trench's papers supported the already growing impetus toward the creation of a new scholarly English dictionary. The result of this movement, the New English Dictionary on Historical Principles or Oxford English Dictionary (NED or OED), primarily edited by James Murray (1837-1915) amid many difficulties, involved the fundamental redesign by its editor of the genre of dictionaries, and was completed in 1928. A biography of Murray by his granddaughter K.M.Elisabeth Murray is almost a creation–history of this great work. A second edition of the OED with about 290,000 main entries and another 157,000 combinations and derivatives, has been in print since 1989. The first edition required the collection of millions of examples and tons of paper slips with quotations from English texts written on them, while the second one is maintained as an enormous computer database, and in a published CD-ROM format the dictionary is computer-searchable.
The OED is a lexical monument and scholarly resource to which there is no parallel for any other language on earth, but it is not affordable or necessary for most people. A smaller and affordable two-volume New Shorter OED (1993) edited by Lesley Brown is remarkably well done, although the earlier versions of the shorter OED edited by C.T. Onions (mostly in single-volume editions) on the basis of the first edition of the OED are in general still highly serviceable.
Two different tracks of development led to the main American unabridged dictionaries. The very small pioneering American dictionary (first edition 1806) of Noah Webster (1758-1843) eventually became the namesake of many American dictionaries. At this time, the term "Webster", by court decision, is simply a generic term for a dictionary and refers to no particular publisher, size, or scholarly standard. The G. and C. Merriam Company (now Merriam-Webster Inc.) developed the scholarly line of Webster's International dictionaries in the later 19th century. Two 20th century unabridged dictionaries from this firm still have great value. They are the Webster's New International Dictionary, Second Edition (1934 and revised reprints) edited by William Neilson and Thomas Knott, with over 550,000 entries, and the Webster's Third New International Dictionary (1961), edited by Philip Gove, with over 450,000 words, for about 285,000 headwords. Both editions were published in several different bindings. The third edition has fewer illustrations and less encyclopedic material than the preceding edition. It also evoked many criticisms at the time of publication, because it was less prescriptive than some dictionaries have been. By this is meant that to some extent it followed the policy that a dictionary should reflect actual contemporary usage rather than instruct writers in usage from a normative point of view. Any dictionary, of course, must steer between these opposite extremes. Both books are superb reference tools, and any institution or professional office in which words or writing are important will want to have both editions.
A second major line of American dictionaries has come from a more complex background. In the mid-19th century, the greatest American specialist in the study of language was the Sanskrit scholar and linguist William Dwight Whitney (1827-1894). He contributed to the Webster's unabridged dictionary published in 1864, and published many important works on Sanskrit, the classical language of ancient India, and its earliest texts. The Century Company engaged Whitney as editor in chief of a great new multi-volume dictionary, The Century Dictionary (CD, first edition 1889-1891). Its second edition of 1901 (one of my prized possessions), with eight volumes of text, one volume of proper names, and a last volume of atlas, contains over 530,000 entries. A two-volume abbreviated edition under the title The New Century Dictionary (NCD) was in print into the 1950s.
Random House obtained rights to use the CD and NCD material, and also that of the Dictionary of American English edited by W.A.Craigie and J.R.Hulbert , and in 1947 published the American College Dictionary (ACD), a smaller intermediate sized dictionary which is distinctive for the quality of its basic lexical material, extensive encyclopedic information, and logical selection and arrangement of its material. It contains about 75,000 headwords. It was edited by Clarence Barnhart, who studied under the great linguist Leonard Bloomfield, and Jess Stein, and it has a modern aspect compared to other American dictionaries published in the same period, because it drew on the advice of a number of distinguished linguists in its construction. It also followed the model of the Merriam-Webster dictionaries in turning to many outside experts on subject matter. It is better, for example, to have your definitions of scientific terms reviewed by scientists than by lexicographers. Although now it is dated in terms of the encyclopedic information and inevitably it lacks modern technical and colloquial terms, the ACD can be easily purchased and is still a work that can be used with profit for most applications where a desk dictionary is convenient.
After the mixed response to the Webster's Third New International Dictionary edition of 1961, Random House expanded the ACD framework into the Random House Dictionary (1966) under the editorship of Jess Stein and Lawrence Urdang. With rich encyclopedic information, and about two-thirds the length of the Webster's International dictionaries, it immediately provided a worthy alternative to the Merriam-Webster's unabridged dictionaries. The second edition of 1987 under the title Random House Unabridged Dictionary (RHUD), with a minor revision of 1993 which claims over 315,000 entries, provided the advantages of an up to date unabridged dictionary plus considerable encyclopedic information, a small atlas, and short dictionaries of common European languages. With several different formats, the lexical material has been reprinted in an inexpensive form as the Random House Webster's Unabridged Dictionary (2nd ed. 2001) with a slightly awkward binding, while a newer deluxe version has an elegant cloth binding and incorporates richer ancillary material. CD-ROM versions can be found. When I gave a copy of the RHUD to a friend who worked as a reporter in a southern newspaper office that relied on a college dictionary, the value of the RHUD was soon recognized and it was labelled as "the Big Dog" in terms of an unprintable southern proverb which expresses dominance. In terms of general utility, lexical breadth, and encyclopedic material, I know of no modern English single volume dictionary that outdoes it. For general reference, it is usually the first work I consult. If my curiosity is still unsatisfied, then I look at the Webster's International dictionaries.
More briefly, we will consider the most common intermediate-size dictionaries that are offered for home usage. The American Heritage Dictionary of the English Language (AHD) was planned after criticism of the Webster's 3rd New International edition (1961) created a market opportunity. The AHD (now in its 4th edition, 2000) was edited by William Morris for Houghton Mifflin, and first appeared in 1969 in an intermediate size, smaller than the Webster's 3rd and larger than the desk or college dictionaries. Its abundant color illustrations in the margin and rich encyclopedic information are distinctive. Usage recommendations, one of its original motivations, are limited compared to e.g. the indispensable Garner's American English Usage (2003).
A distinctive feature is a fascinating appendix by one of my teachers, Calvert Watkins, on the Indo-European language which is the source of most of our English words, with an analysis of most etymologies in terms of the roots from which words are derived, and a dictionary of Indo-European roots, a unique feature now supplemented by a appendix and dictionary on Semitic roots.
A second noteworthy dictionary in this intermediate size range is the Encarta Dictionary of World English (1999), edited by Kathy Rooney as editor in chief with Lesley Brown (editor of the New Shorter OED) as the senior lexicographer. Contemporary linguists have profited from the opportunity to use computer data-bases incorporating enormous quantities of English written texts instead of the tons of paper slips that went into the original OED. The Encarta dictionary, with about 100,000 main entries, provides outstanding coverage of contemporary English. It is the first place that I look for modern colloquial phraseology and slang, which earlier was covered by the now dated dictionaries of slang by Eric Partridge. It is well illustrated and includes much encyclopedic information.
Dictionaries can be precious resources if you learn the strengths of each. A very browsable and enjoyable further guide to this general area, which has been drawn on here, is Tom McArthur's Oxford Companion to the English Language (OUP, 1992).