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From the Oxford Classical Dictionary

As in many areas of corporate activity, best practice in publishing seems to suffer from amnesia. Good principles are established in one generation, then, for no apparent reason, lost. Publishers come and go, and perhaps new publishers don’t pick up the principles that the older publishers had. Whatever the case, the principles for compiling reference works seem constantly to be forgotten, and have to be rediscovered.

In this post I aim to provide a few basic principles for writing reference entries. Don’t think that digital publishing has removed the need for reference. Defining terms remains a core requirement for all academic learning, and digital publishing should simply bring the definitions closer to where readers need them – in their reading.

Don’t be surprised if nothing you read here is new. The principles have been around for years, and yet Wikipedia, among others, is still learning them. I will include some examples from Wikipedia to show where they get it wrong (and, to be fair, where they get it right).

Years ago, when I was managing an encyclopedia compilation and revision operation, with over 100 contributors, we needed a concise summary of how to write an encyclopedia entry. The resulting notes are a reassembly of those points – the original instructions were lost many years ago. What is remarkable, despite the shift in reference publishing to digital, is how the same principles apply to writing reference content today – and is ignored in well-regarded source such as Wikipedia.

Finally, almost all these principles are the same as for writing a dictionary definition. Why reference and encyclopedia publishing continually fails to notice how a good dictionary works is one of life’s mysteries.

Principles of defining (adjusted for encyclopedia content)

  • Begin with a definition: an X is a Y. Do not begin with an example.
  • Make the initial entry as concise as possible. Do not use “name given to”, or other words that do not add meaning to the definition. Keep more discursive content (if included) in subsequent paragraphs
  • Avoid circular definitions – defining something using the same term as what is being defined.
  • Define every word used in the definition. That doesn’t mean you cannot use cross-references, but if essential for understanding, the cross-reference should also be explained in context. Otherwise the user seeking to understand one word finds him- or herself looking up several. This is especially true for technical terms. Technical accuracy may be less important than intelligibility, at least for the initial definition.
  • Don’t use value terms such as “important”, “influential”, “world-famous”, because they don’t explain. They force the reader to substitute trust (I trust this source) for understanding (I understand why this guy is significant).
  • Particularly for encyclopedic content, follow the onion-skin principle: make the first part of the entry, typically the first sentence, accessible to the widest possible audience. Then add more sophisticated explanation in subsequent paragraphs, which may qualify or extend the initial description. This frequently means that the topic is discussed several times, with an increasing level of precision and complexity each time. World Book is very good at this kind of entry.

These principles apply for a concise subject dictionary, averaging just 50 or 100 words per entry, right up to a large-scale encyclopedia, of 500 or more words per entry. Both should begin with a short, clear definition.

Good and bad examples

Here are some examples. Wikipedia has many entries for animals, bird and plants. Many of these appear not to have been written by average Wikipedia editors, but by students or academics in the respective areas; I believe that some academic departments encourage the use of Wikipedia as a collectively-written reference source, which is admirable. However, the technical language that students and faculty understand, and what the average reader understands, are very different. This is a similar problem to that experienced by dictionary compilers. They want entries for “content” words to be accurate, so they hand the task of writing definitions for animals, birds and plants to a scientist … who then creates definitions that are 100% accurate yet 100% unintelligible to the general reader.

I noticed this when recently reading Darwin’s Voyage of the Beagle, a book published in 1839, and full of references to individual species. It seemed obvious to look these up in Wikipedia, and yet I found the descriptions in Darwin often far more intelligible to the average reader (me) than many Wikipedia articles on the same topics. For example:

Crested caracara … The cap, belly, thighs, most of the wings, and tail tip are dark brownish, the auriculars (feathers surrounding the ear), throat, and nape are whitish-buff, and the chest, neck, mantle, back, upper tail coverts, crissum (the undertail coverts surrounding the cloaca), and basal part of the tail are whitish-buff barred dark brownish.[ Wikipedia, article for Crested caracara, accessed 24 Sept 2022]

Here ”crissum” and “auriculars” are cross-references but also explained here. However, other terms such as “coverts”, “cloaca” are not (and should be).

The great kiskadee (Pitangus sulphuratus), called bem-te-vi in Brazil and benteveo in Argentina, is a passerine bird in the tyrant flycatcher family Tyrannidae. [Wikipedia entry for Great kiskadee, accessed 24 Sept 2022]

If I don’t know “passerine”, I have to look it up. The Wikipedia entry for “passerine” states that “a passerine is any bird of the order Passeriformes … sometimes known as perching birds, distinguished from other orders of birds by the arrangement of their toes (three pointing forward and one back, which facilitates perching.” So I would change the great kiskadee definition to read:

The great kiskadee (Pitangus sulphuratus) … is a passerine (perching) bird in the tyrant flycatcher family Tyrannidae.

Here are some other examples of technical terms obscuring the meaning:

European robin … it is sedentary in most of its range except the far north.[Wikipedia, entry for European robin]

“Sedentary”, when I look it up (the article is actually “sedentism”, means “the practice of living in one place for a long time”. So I would gloss this as “it does not migrate”.

Passerine … With more than 140 families and some 6,500 identified species,[1] Passeriformes is the largest clade of birds [Wikipedia, entry for “Passerine”]

What is a clade? If I don’t know what “passerine” means, I probably don’t know what a clade is.

Subject-specific encyclopedias

The same principles of definition apply here, but within the context of the subject-specific collection. For example, I might want to see why Cicero, the Roman orator and lawyer, was so popular during the Renaissance. So I looked him up, not in a general encyclopedia, but in a subject-specific reference book that answers my specific question. Here, the first definition I found is a real shocker, from The Thames and Hudson Encyclopedia of the Italian Renaissance (1981, but still in print, apparently):

Cicero, Marcus Tullius (106-43 BC) For Dante it was one of the miracles of God’s intervention in the history of Rome that Cicero defended its liberties against Catiline; but Cicero is not an important author for Dante…

This is how the entry begins! Who is Cicero? Why is he relevant to a book about the Renaissance? Sadly, the reader has lost interest  and failed to get the required information before proceeding further in this article (which states some interesting things in a very elliptical way).

Let’s try another source, The Encyclopedia of the Renaissance, Scribner, 2000, six volumes)

Cicero Roman statesman, orator, writer whose work influenced Renaissance thought and literature.

This is much better – it tells you who Cicero was, but it misses the opportunity to provide genuine insight. It says Cicero “influenced” the Renaissance, but can we not say in what way? Better would be to state (as I discovered from the T&H Encyclopedia) that Cicero was the model of eloquence for Renaissance writers.

Further reading

The above rules are not original; at least, there are plenty of guides to writing dictionaries. A good outline, such as Sidney Landau’s Dictionaries: the art and craft of lexicography (1984, second edition 2001), gives clear and simple recommendations for writing definitions. Landau states quite openly he got his principles of definition from the wonderfully named author (who was no doubt always placed last in every grouping at school) ) Ladislav Zgusta, Manual of Lexicography, 1971. Both of these sources have been greatly expanded in more recent lexicography manuals, for example The Oxford Guide to Practical Lexicography, 2008, but this book takes 47 pages (pp 405-452) to provide a few principles for defining; this is not so much a manual as a discursive read for those with plenty of leisure time.