This dictionary combines six separate public-domain sources, each from a different era and tradition, plus a set of illustrations drawn from a seventh. Details on each are below.
Public-domain text of Webster's Revised Unabridged Dictionary (1913), via OPTED (The Online Plain Text English Dictionary), a project of the Australian National University.
The 1913 edition was the last major revision published under the "Webster's International" name before the dictionary's copyright and branding were split apart by later publishers. It represents the fullest, most formally standardized state of the Webster's tradition — comprehensive definitions, etymology, and usage notes reflecting late-19th and early-20th-century American English.
Entries from Noah Webster's An American Dictionary of the English Language (1828).
This is the founding work of American lexicography. Noah Webster spent roughly two decades compiling it, reportedly learning 26 languages — including Anglo-Saxon and Sanskrit — to trace word origins more rigorously than any English dictionary before it had attempted. It also deliberately broke from British spelling conventions (color instead of colour, honor instead of honour, center instead of centre), spellings that remain standard American English today.
Entries from the 9th edition of the Encyclopædia Britannica: A Dictionary of Arts, Sciences, and General Literature (25 vols., 1875–1889), via the Nineteenth-Century Knowledge Project (Temple University), used under a Creative Commons Attribution 4.0 International License.
Known as "the Scholar's Edition," the 9th edition is widely considered the high-water mark of Britannica's scholarly reputation. Roughly 1,100 contributors wrote for it, including a number of genuinely famous names of the era — Thomas Henry Huxley, Robert Louis Stevenson, Algernon Charles Swinburne, and Lord Rayleigh among them. Many entries are individually signed with the contributor's initials, a practice this dictionary preserves and displays where available — 503 distinct signatures survive across 1,385 articles in this collection.
Some entries are less "encyclopedia entry" and more full-length treatise. The article for "Geology" alone runs to roughly 206,000 words — longer than most novels.
Entries from Richard Watson's A Biblical and Theological Dictionary (1833), via Project Gutenberg.
Watson was a Wesleyan Methodist theologian, and his dictionary reflects that tradition — the entries are as much doctrinal essays as they are definitions. Where Webster tells you what a word means and Britannica tells you what a subject comprises, Watson tells you what to believe about it. His entry on "Aaron," for instance, runs to over a thousand words and covers not just the biblical figure but the typology of the Aaronic priesthood as a foreshadowing of Christ. It is a document of its era and its religious tradition, and is presented here as such.
The text of the King James (Authorized) Version in its standardized 1769 form, including the Apocrypha, from eBible.org (courtesy of the Crosswire Bible Society and eBible.org), as distributed in the open-bibles repository. It is in the public domain. (Letters patent issued by King James restrict printing this translation in the United Kingdom; they have no effect anywhere else.)
By default this is the text behind the verse tooltips and verse links in the dictionary and encyclopedia entries, and behind the Bible verse search results. The Apocrypha are arranged as the King James Bible prints them — for example, the Epistle of Jeremy is chapter 6 of Baruch — because that is how the older sources here cite them. Psalm titles are kept apart from the numbered verses, as in the printed King James Bible.
The Berean Standard Bible (BSB) is a modern-English translation, offered here as an easier-reading alternative. Under Settings → Bible version you can choose the King James Bible, the BSB, or both side by side. The text is used as published at berean.bible, via the scrollmapper/bible_databases repository; footnotes and section headings are left out. The Holy Bible, Berean Standard Bible, BSB is produced in cooperation with Bible Hub, Discovery Bible, OpenBible.com, and the Berean Bible Translation Committee. This text of God's Word has been dedicated to the public domain. (It was dedicated on April 30, 2023, and all uses are freely permitted.)
The BSB is numbered exactly like the King James Bible, so a reference such as “Rom. viii. 28” in an older entry points to the same verse in either translation. Sixteen verses that the manuscripts behind the BSB leave out (for example Matthew 17:21 and Mark 9:44) are marked as not in the BSB. The BSB has no Apocrypha, so references to those books show the King James text.
Psalm 119, at 176 verses, is the longest chapter in the King James Bible.
The 1911 edition of Peter Mark Roget's Thesaurus of English Words and Phrases, via Project Gutenberg, transcribed by MICRA, Inc. It is in the public domain.
Worth knowing: this is not a pure, unmodified transcription of the 1911 print edition. MICRA's own header for the file states it was “supplemented with over 1,000 words not present in the original 1911 edition.” No freely available machine-readable transcription of an earlier edition (Roget's own first edition of 1852, or his son's 1879 revision) could be found — only page scans, which would need fresh proofreading before they could be used here. This is the closest usable public-domain text of the book, not a perfect facsimile of any single historical printing.
Roget organized the book by concept rather than by word — 1,043 numbered categories such as §17 “Similarity” or §897 “Love,” each listing the nouns, verbs, adjectives, and phrases that belong to it. Searching a word here finds every category it appears in, then shows that category's full list, the same way flipping to a page in a printed Roget's shows you everything grouped there, not just the one word you looked up. Nothing has been left out for being obsolete, archaic, or foreign: every word MICRA's transcription marked obsolete, and every Latin, French, German, Italian, or Greek phrase, is included and labeled exactly as transcribed.
One entry (category 194, adjectives) reproduces a dropped closing parenthesis found in MICRA's 1991 transcription itself — confirmed against an identically worded, correctly punctuated cross-reference a few lines earlier in the very same category — and corrected to match it. Every other bracket, tag, and cross-reference in the text is preserved exactly as transcribed, including its genuine peculiarities.
Illustrations from Webster's New International Dictionary of 1890 and 1900.
These were extracted from full-page scans by an automated process, which sometimes misreads a caption or crops imprecisely. Each one was then reviewed by a human and kept or discarded based on the quality of that machine-made crop — not on how well it actually illustrates the underlying word. Where a word appears in both the 1828 and 1913 editions, an illustration's placement is currently biased toward 1828 simply because that edition happens to be returned first by the underlying database query, not because of any judgment about which edition it suits better. This is an ongoing curation process, and both the crops and their placement will keep improving over time.
