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Glossary of Geology, Fifth Edition Revised

The Glossary of Geology is available in many formats. Please select the format below for more information:

Kindle or Nook E-Book
Online IP Subscriptions (institutions and businesses only)



AGI is proud to feature this Fifth REVISED edition of the Glossary of Geology. This indispensable reference tool contains nearly 40,000 entries, including 3,600 new terms and nearly 13,000 entries with revised definitions from the previous edition. The revisions represent both advances in scientific thought and changes in usage and they make this 800+ page hardbound a must for any earth science professional or student. In addition to definitions, many entries include background information and aids to syllabication. The Glossary draws its authority from the expertise of the more than 100 geoscientists in many specialties who reviewed definitions and added new terms. Click here to order from us or you may order from Amazon.

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Kindle eBook

The entire contents of the Glossary of Geology 5th Edition, Revised is available as a Kindle E-Book. With all content and formatting from the hardcopy version faithfully reproduced, you get the browsing experience of the hardcopy with the searchability* and portability of an eBook.  Available at half of the list price of the hardcopy, the eBook version is your perfect companion.

*Please note: Initial search indexing by your e-reader may take up to a day to complete. This is a one-time cataloging of the e-book that will occur as a background process, and make future searches occur more quickly. For the first 24 hours, search results may be incomplete.

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Online Subscriptions

The Glossary of Geology is available as an online subscription, via IP address, to libraries, university departments, corporations, etc. 

The online Glossary provides access to the more than 39,000 glossary entries contained in the Fifth Edition of the print Glossary. In addition to the 13,000 updated entries that appeared in the Fifth Edition, more than 1100 changes, deletions and additions have been made to the online version since the publication of the print edition -- making the online Glossary even more up-to-date.

Users can learn the difference between look-alike pairs, such as sylvanite (a mineral) and sylvinite (a rock); the origin of terms; the meaning of abbreviations and acronyms common in the geoscience vocabulary; the dates many terms were first used; the meaning of certain prefixes; and the preferred term of two or more synonyms. Many Glossary entries contain a syllabification guide and background information.

The online Glossary is searchable using terms, words within terms or definitions, categories and Spanish-language equivalents. Boolean operators (and/or/not) are available for each search field. Search fields may also be combined or may be browsed using a pop-up word wheel.
The online Glossary includes several features not available in the print version:

  • Display option for images of minerals, rocks, fossils and landforms. These images are drawn from the Earth Science World Image Bank maintained by AGI.
  • Spanish language equivalents for many entries in the online Glossary. Translated by geoscientists whose native language is Spanish, the Spanish entries can be browsed or searched directly.
  • Hyperlinks to related or similar terms. Synonyms or antonyms and glossary terms appearing as parts of other term definitions are frequently hyperlinked to allow quick reference.

The online Glossary is an annual subscription. The rate is based on users. For a quote, or to inquire about site-wide licensing, please email

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