encyclopedia
Pluralencyclopedias, encyclopediae, encyclopediæ
UK spellingencyclopaedia
- 1A comprehensive reference work with articles on many subjects, or on a single field, arranged alphabetically or by category, whether printed in volumes or published on disc or online.
The family bought a twenty-volume encyclopedia from a door-to-door salesman.
The library keeps a medical encyclopedia in its reference section.
UsageYou look something up in an encyclopedia. The plural is encyclopedias.
Note
The reference book has landmarks you can date. John Harris's Lexicon Technicum (1704) was the first in English with its articles in alphabetical order, and d'Alembert's preliminary discourse of 1751 introduces an Encyclopedia written by "a society of men of letters".
Checked 2 Nov 2026 · 4 facts
- John Harris compiled Lexicon Technicum, whose first volume was first published in 1704. en.wikipedia.org
- Lexicon Technicum was the first English encyclopedia with alphabetically arranged articles. en.wikisource.org
- D'Alembert wrote the preliminary discourse published in 1751. encyclopedie.uchicago.edu
- The discourse introduces the Encyclopedia as the work of a society of men of letters; the quoted English wording is a translation. en.wiktionary.org
- 2The whole circle of the arts and sciences, or a comprehensive summary of all knowledge or of one branch of it.
All of the Indo-European languages treated in this encyclopedia are included in the alphabetic list of families and other large groupings in the last section of this article.
2006, B. J. Blake, “Classification of Languages”Similarcompendium
Note
The image is in the word: Greek enkuklios, "circular" (from en, "in", and kuklos, "circle"), joined to paideia, "education", picturing all learning as one round of arts and sciences. The reference books took their name from that ideal.
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Origin
Ancient Greek enkúklios ("circular") and paideíā ("childrearing, education") formed the Koine Greek phrase enkúklios paideíā, meaning an education covering "the circle of arts and sciences." New Latin joined it into one word, encyclopēdīa or encyclopaedīa ("general education"), and English borrowed that. Nearly all modern English use follows the scope and format set by Diderot and others in the French Encyclopédie.