Encyclopedia
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An encyclopedia is a reference work or compendium providing summaries of knowledge, either general or special, in a particular field or discipline. Encyclopedias are divided into articles or entries t
A laptop shows a Wikipedia page on "Encyclopedia", beside stacked volumes and an open page of the Encyclopædia Britannica.
Pliny the Elder's Natural History is one of the oldest extant encyclopedias.
The Yongle Encyclopedia is the largest paper encyclopedia of world history
Britannica 15th edition printed encyclopedias, 2002
Thesaurus
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A thesaurus, sometimes called a synonym dictionary or dictionary of synonyms, is a reference work which arranges words by their meanings, sometimes as a hierarchy of broader and narrower terms, someti
Thesaurus Linguae Latinae
A modern English thesaurus
Peter Mark Roget, author of Roget's thesaurus