Wikipedia:Dictionaries as sources

Wikipedia generally prefers secondary sources in support of articles. It has a policy distinguishing among primary, secondary, and tertiary sources. Dictionaries and glossaries present a special challenge in determining whether the source is primary, secondary, or tertiary. One dictionary or glossary may be considered a primary source among linguists, whereas for Wikipedia's purposes it is a secondary source. Another dictionary or glossary that among linguists is considered derivative, and thus secondary, is likely considered a tertiary source for Wikipedia's purposes. Additionally, some glossaries are considered primary sources for Wikipedia's purposes.

Dictionaries have limits to their utility. In general, the earliest known usage of a word cannot be definitively determined using a dictionary alone, and the same is true of stylings, such as hyphenated or open formats. Additionally, definitions are separate from etymologies; to use a centuries-old etymology as a modern definition is a mistake, and while dictionary definitions are usually reasonably precise, they are not necessarily mathematically precise for every word.

Dictionaries vs. glossaries
Technically, a glossary is a kind of dictionary which is limited to the vocabulary of a particular specialty. For example, when defining the phrase "take two aspirin", a medical glossary might define only the word aspirin, whereas a dictionary would be more likely to define each word separately (take, two, and aspirin).

Oftentimes a glossary serves as a supplemental material; for example, there is usually a glossary at the back of a textbook. Other times, a glossary may be long enough to be bound as a standalone book. Confusingly, these glossary books are often called dictionaries regardless of their scope; for example, there are several medical glossaries that are called dictionaries by their publishers.

For the purpose of this essay, dictionaries and glossaries are treated alike.

Evaluate overall, not by single entry
A dictionary is classified by its overall character. For instance, the original Oxford English Dictionary ([1st ed.] 1933) is generally a primary dictionary (and is secondary for Wikipedia), yet reportedly at least one of its entries is not based on any identified source. That particular entry was provided by the dictionary's editor, who felt enough certainty of the word's existence and usage to justify adding it without citing evidence. It would probably be absurd to classify that dictionary as less than a primary source simply because of that one entry.

Likewise, a children's dictionary, which is generally derivative and thus a secondary or tertiary source for Wikipedia, could have cited a published source for one of its entries, and yet it should not be considered a dictionary primary source among linguists just because of the one exceptional entry.

A dictionary's value as a source should not be determined by the list of people (famous or otherwise) that were involved in editing it, especially if the people are listed as "advisors," because the actual roles of such people are nearly impossible to determine.

Specialized, online, multivolume, and old dictionaries
When determining whether a dictionary should be considered a primary, secondary, or tertiary resource on Wikipedia, any specialized, online, multivolume, or old dictionaries must be judged by the same standards as a standard print dictionary.

Types of specialized dictionaries include: and more.
 * professional (ex. a medical dictionary),
 * dialectal (dialect),
 * slang or neologistic (new-word),
 * phrasal (phrase),
 * grammatical,
 * thesaural,
 * etymological,
 * biographical,
 * encyclopedic,
 * foreign (non-English) language,
 * bilingual,
 * polyglot (multilingual),
 * reconstructive (for long-dead unwritten or unattested languages),
 * reverse symbolic,
 * picture-to-word,

Online dictionaries should be judged the same as offline dictionaries.

A dictionary which is called "unabridged" is a little suggestive, but not prohibitive; the same goes for the number of volumes.

Age is also not inherently prohibitive; however, if a dictionary has been succeeded by a newer edition, it may no longer be a reliable source for Wikipedia.

A dictionary's fame (or lack thereof) should not matter; in fact, some lesser-known dictionaries can be especially authoritative.

Dictionaries with insufficient standards, consistency, or enforcement
A dictionary that does not have or enforce many standards for publication is probably not a reliable source for Wikipedia. A wiki-based dictionary that anyone can edit without editorial oversight is not reliable--and that includes Wiktionary.

Also of note: In the modern day, the name Webster (or Webster's) is used by such a wide variety of publishers that it no longer signifies a specific publisher, brand, or level of quality, and thus should not be used as evidence in favor of a source's reliability.

Articles about dictionaries don't much matter
For dictionary to have a designated Wikipedia article, only notability is required. It makes sense that Wikipedia articles about dictionaries may cite the respective dictionaries, but in cases where a word used somewhere on Wikipedia needs to be supported by a citation to a dictionary, focus on whether the dictionary to be cited for that word is actually acceptable as a reliable source under the policies and guidelines for citing on Wikipedia, rather than whether the dictionary is the subject of an article.

Dictionaries that are primary for Wikipedia
When entries are based on contributors' personal experiences, the dictionary is a primary source for Wikipedia. If someone, drawing on personal experience, invents a set of words and meanings and writes a dictionary of those inventions, that dictionary is based on the author's personal experience and thus is primary for Wikipedia. (It is also primary to linguists, but that is a different meaning of primary.)

A dictionary that is part of a novel, or of fictional media (such as a film, TV show, or game) is a primary source for Wikipedia. However, a dictionary written by a scholar about words invented in a novel or fictional film, TV show, or game may be secondary, provided that the scholar has done an independent analysis and not simply copied the entries.

Words and meanings from a source that is primary for Wikipedia could hypothetically become part of a language, and then appear in a dictionary, which would then be secondary or tertiary for Wikipedia. For example, imagine a scenario where a sports leader invents a new game, and invents descriptive names for various game elements (such as actions, player roles, pieces, etc). The sports leader then publishes a dictionary of the invented nouns and verbs. A reliable scholar or publisher then sees this dictionary and adds words from it to a reliable, authoritative dictionary. The sports leader's dictionary would then be considered primary among linguists, and the sports leader's words would be defined in an authoritative dictionary, which is a source that is secondary for Wikipedia.

Dictionaries that are secondary for Wikipedia but primary among linguists
If a dictionary relies on publications, broadcasts, spoken words, and similar kinds of sources plus analysis by the dictionary's editors analyzing those sources to identify and provide words, spellings, inflections, dates, whether current, meanings, etymologies, pronunciations, functionalities, registers, and so on, the analysis being based on those sources and on general scholarship, but not on personal experience or invention, makes the dictionary a primary dictionary to linguists and secondary for Wikipedia.

Not all dictionaries make their primacy self-evident. Some cite sources in most entries, and such dictionaries are probably primary authorities among linguists and secondary for Wikipedia. Some may cite only authors or other sketchy information, and those dictionaries may well still be primary among linguists and secondary for Wikipedia. Some may only describe their methodologies in their frontmatter, which requires a judgment that the frontmatter is not false or excessively hyperbolic; if the frontmatter is more detailed, it may be more trustworthy, but that has to be judged for each dictionary.

For English, such dictionaries include the Oxford English Dictionary (OED), Webster's Third New International Dictionary (Merriam-Webster) (W3), the Dictionary of American Regional English (DARE), and the Random House Historical Dictionary of American Slang (HDAS).

Some smaller dictionaries offered by the publishers of larger editions may also be primary among linguists and secondary for Wikipedia. For example, the Shorter Oxford English Dictionary ([4th] ed.) (SOED) apparently relies on publications for determining entries, yet is smaller than the Oxford English Dictionary because the SOED omits many words the OED carries because they haven't been found in recorded English in recent centuries.

Some derivative dictionaries (which are secondary among linguists and tertiary for Wikipedia because their content generally comes from more authoritative dictionaries and not directly from literature, speech, or other primary sources) contain nonderivative primary content. That happens when they contain one or more entries based on primary sources, especially likely with words that are too new to have been entered into a nonderivatve dictionary that is primary among linguists and secondary for Wikipedia. However, such dictionaries rarely, if ever, tell you which word entries are nonderivative. If you cite a derivative dictionary for information for which a nonderivative dictionary is needed, you will have to establish that the particular information is nonderivative or your content may be unauthorized synthesis, a policy violation.

Dictionaries that may be tertiary for Wikipedia but are secondary among linguists
Many dictionaries are based on other dictionaries. These are derivative dictionaries. Children's, student, and collegiate dictionaries, dictionaries offered for people just starting to learn English or learning to read, reverse dictionaries for finding words when all you know is a definition and for solving crossword puzzles, and dictionaries meant for word games like Scrabble will almost always be derivative. It does not matter whether the same publisher has more authoritative dictionaries or not; a dictionary may have been derived from other publishers' dictionaries. Derivative dictionaries are secondary among linguists. Whether they're secondary or tertiary for Wikipedia depends on each dictionary.

Etymology as modern restraint
Defining a word according to its etymology is a frequent descriptivist error. It seems sensible, but meanings can change at any time, whereas attestable etymologies are only discovered later and otherwise hardly change.

The belief that how a word was used at its beginning or in a certain long-ago time and place is how it should be used today, a prescriptivist error, may be valid for some words in some contexts, but not for most of them most of the time. It's not even the case for most words that came from, say, Latin. People have new needs. Language grows with us. Language is learned, therefore cultural, and culture includes other practices, such as slavery. We don't continue enslaving people today just because slavery used to be a respected tradition. How we ask people to work and whether we pay them changed. Words, too, change over time.

Definitions as precise
Most well-known words are defined only approximately and most synonyms are only near-synonyms. Exceptions with precise definitions include some mathematical and scholarly terms, some new terms, and some terms that are rarely used. But, for example, it's becoming common to place intensifying adjectives in front of unique, as in very unique, indicating that in popular use unique is understood to be inexact, and that pattern is true for many words in widespread use. A definition for nice normally is not exactly precise and that has not stopped most people from saying the word perhaps a few times a day, on average. If precision is desired, generally it's more pragmatic to seek greater precision, not perfection, and to consider using a phrase or a paragraph instead of searching for just the right lonely word.

Dates for words in dictionaries
Some dictionaries give the earliest known dates for a word or for one of its meanings, functionalities, or spellings. Some people mistakenly believe that the word, meaning, or spelling did not exist before that date. However, usually the date is only of the earliest evidence known to the dictionary's editors. Relatively few words, meanings, and spellings are deliberately coined on the record and then widely adopted into English, such as if a chemist invents a chemical and names it. Instead, most words, meanings, and spellings evolve with little notice, often rejected as mistakes before repetition and acceptance.

The date may be of only linguistic interest anyway. A word may simply replace a short phrase. To a nonlinguist, the difference may be trivial. Whether a word or a phrase was in use, the defined concept may already have had a handle that people were using before the new word was invented, assuming the date is accurate. So the concept may already have been communicated, and that may be more important than the word.

Most children doubtless don't know the definition of floccinaucinihilipilification but most children practice it for years without batting an eye. There are societies whose adults have no name for the color we English speakers call purple, but that doesn't mean that no flower where they live could be purple. If something got a name in one year, the thing could still have existed in earlier years; we agree on pre-name existence for neutrons. The color or the neutrons could possibly have been identified by a phrase or a paragraph long ago, and dictionaries might not list that. And matters that are rarely discussed don't need efficient tools for discussion (i.e., single words) and that which only a few people discuss may never be heard of by any dictionary editor, yet in both cases they are discussed by people despite dictionaries' universal silence.

Hyphenated, set solid, or spaced
The same word may appear styled in only one way in a dictionary but in two or three ways in English texts. The only difference in spelling, function, and meaning may be in the spelling having a hyphen, a space, or neither (set solid). (Linguists recognize as a single word a spelling that includes a space, such as open up in "it's time to open up the store", because open up behaves linguistically like a single word even if a word processor's spelling checker doesn't recognize it.) When a dictionary gives only one of these stylings, the choice may have been arbitrary or change may have occurred over time, but other stylings may be valid. Exceptions are rare; an exceptional set is sweetbread and sweet bread, which have different meanings.