The dictionaries with which most people are familiar list, in varying degrees of comprehensiveness, the words in a language, providing their standard and alternative spellings and definitions. There is a general perception among the public that dictionaries should be authoritative guides to language. This view holds that the spellings and usages contained in a dictionary are correct, and that those that are not are incorrect. Therefore, if a slang locution such as “ain’t” is not listed in a dictionary, it should not be used.

The earliest English language dictionaries often veered toward a kind of whimsicality that reflected the backgrounds and prejudices of their compilers. Samuel Johnson’s A Dictionary of the English Language (1755), for example, defined “oats” as “a grain that in England is generally fed to horses, but in Scotland supports the people.” Variant spellings were more common and more widely tolerated before the eighteenth century than they were after it, largely because of increased public literacy and the proliferation of standardized spellings in printed material.

In addition to the general, word-definition dictionaries with which most people are familiar, specialized dictionaries exist that focus on specific vocational or other areas. Some dictionaries emphasize such aspects of language as etymology, pronunciation, dialects, or synonyms and antonyms. Others offer such encyclopedic information as that found in biographical or geographical dictionaries. Still others provide bilingual equivalencies for non- native speakers of a language, such as those found in bilingual dictionaries.

Until 1961, when Webster’s Third International Dictionary was published, dictionaries were largely prescriptive. That is, they set standards of usage, provided rigid rules for spelling, and essentially dictated how language should be used properly. Webster’s Third International Dictionary was the first wholly new unabridged dictionary produced by the Merriam-Webster Company since 1934. Earlier dictionaries were typically built around the principles of a Latinate grammar that did not easily accommodate the conventions of English, which is a Germanic, rather than a Romance, language. As a result, many dictionary users found their prescriptive rules difficult to apply to the realities of English language.

During the 1940’s and 1950’s much was learned about language by those who had taught intensive language courses to the military during World War II. Language came to be viewed more as something alive and dynamic than as something static with a fixed set of rules whose violation represented—at least in the public mind—grammatical errors. Since that time, modern grammarians have advanced the idea that any language that communicates successfully is grammatically acceptable, regardless of whether or not it is socially acceptability.

To grammarians concerned with describing language, a phrase such as “I ain’t got none” communicates the idea that its speaker intends just as well as “I do not have any” (or “I have none”). One level of society tends to use locutions such as the former, while another uses the latter. The old prevailing belief that two negatives (“ain’t” and “none”) necessarily make a positive may be accurate in mathematics, but it is absurd in real English usage. Even such revered writers as William Shakespeare often achieved emphasis by using double (or triple or quadruple) negatives.

The word order and sentence structure in both sentences cited above are standard. Neither is grammatically incorrect when viewed in the context of modern descriptive grammar. An utterance that is truly grammatically incorrect might be something such as “I store to the went”—a statement that no native speakers of English would ever make, regardless of their social or educational levels.

Modern lexicographers have been almost unanimously descriptive, rather than prescriptive, in their approaches to dictionary making. The public at large, however, has been slow to catch up with them. It was for this reason that after Webster’s Third International Dictionary appeared that subsequent dictionaries such as Webster’s Seventh New Collegiate Dictionary (1963) and The American Heritage Dictionary (1969) were designed to be considerably more prescriptive than Webster’s Third had been.

The editorial board of Webster’s Third and its chief editor, Philip B. Gove, refused to make moral judgments about many words and usages that earlier editions had dismissed as slang, colloquial, or substandard English. Because modern linguists consider spoken language more reflective of true usage than written forms of the language, citations of authority for many usages in Webster’s Third were made to popular entertainers such as Marilyn Monroe or Elvis Presley, rather than to the hallowed literary sources used cited in dictionaries. This was a departure that disturbed many of the edition’s critics.

Although most modern dictionaries contain words that are at least mildly profane, they usually do not contain words that are considered obscene, despite their pervasive presence in modern literature, as well as a not inconsiderable body of English writing dating back to the Middle Ages. Description of coarse words has generally been left to more specialized reference works, such as the Dictionary of American Slang (first published in 1960) and the New Dictionary of American Slang (1986). There has, however, been a trend toward including words of every stripe in comprehensive dictionaries. The Oxford English Dictionary (1884-1928), for example, is a compendious multivolume dictionary that carefully traces the history of every word it defines. It has always striven for completeness, but it did not originally include many vulgar words, such as those commonly used to describe sexual acts. Modern revisions of this very inclusive dictionary, have, however, become even more inclusive.

After the Dictionary of American Slang was first published in 1960, it was summarily banned from the public and school libraries in several states—including California and Texas. Max Rafferty, California’s state superintendent of schools in the late 1960’s, publicly railed against the book, attracting such attention that the resulting furor spurred the book’s sales to many people who otherwise would probably not have been aware of its existence.

The most frequently sold dictionaries are single-volume works, such as those typically purchased by students and secretaries. Unabridged dictionaries might contain as many as 600,000 entries, but editors of smaller dictionaries must exclude from their editions whole categories of terms. At times the editors make censorship decisions of sorts, typically by omitting potentially offensive terms. Otherwise, such dictionaries usually omit technical terms that can be found readily in specialized works designed for such fields as medicine, law, or engineering. Many small dictionaries eliminate whole sections, such as the biographical entries or geographical gazetteers typically found in larger dictionaries. Some dictionaries, such as The American Heritage Dictionary, incorporate biographical and other specialized entries into their main texts, conserving space by condensing the definitions greatly.

Most purchasers of single-volume dictionaries expect these editions to be authoritative and are generally unmoved by the explanations and justifications that grammarians and linguists make about language usage. Publishers of such volumes are thus constrained by the demands of the books’ users from radically departing from prescriptive approaches.

A good starting point for research into dictionaries is Yakov Malkiel’s Theory and Method in Lexicography (Ann Arbor: University of Michigan Press, 1980)—a broad discussion of how dictionaries are constructed. Herbert C. Morton’s Philip Gove’s Controversial Dictionary and Its Critics (New York: Cambridge University Press, 1994) offers a detailed account of Philip Gove’s vision for Webster’s Third International Dictionary, and captures well the firestorm that his dictionary ignited. Another good overview of the controversy can be found in the essays collected in Dictionaries and That Dictionary (Chicago: Scott, Foresman, 1962), edited by James Sledd and Wilma R. Ebbitt. Censorship: A Threat to Reading, Learning, Thinking (Newark, Del.: International Reading Association, 1994), edited by John S. Simmons, contains twenty-one articles that provide a comprehensive view of school censorship in the modern United States. Herbert N. Foerstel’s Banned in the U.S.A.: A Reference Guide to Book Censorship in Schools and Public Libraries (Metuchen, N.J.: Scarecrow Press, 1994) cites many instances of school and library censorship.