HomeDictionaries, Glossaries, & Thesauri
Medical
MedlinePlus Medical Dictionary
This is an excellent medical dictionary from the National Library of Medicine.
Glossary of Terms in Managed Care
This managed care glossary provides definitions of commonly used terms by the medical provider, and in the hospital and managed care industries.
Medical Dictionary
This online medical dictionary compiled by physicians includes standard medical terms as well as scientific terms, abbreviations, acronyms, and historical medical terminology.
Glossary of Terms and Symbols in Pharmacology
Created by the Department of Pharmacology and Experimental Therapeutics, Boston University School Of Medicine. Alphabetical listing of terms and symbols used in pharmacology. Terms are not searchable by keyword, however numerous links to cross-references within the glossary are provided.
Multilingual Glossary of Technical and Popular Medical Terms in Nine European Languages
Glossary allowing users to browse technical and medical terms by language.
Science
Biology Online Dictionary
This Web page includes a dictionary of biology terms in addition to biology tutorials and a directory.
EurekAlert! – Dictionaries
This online Reference Desk from the American Association for the Advancement of Science provides dictionaries and other reference help in various scientific areas.
Dictionary of Units
This provides a summary of most of the units of measurement to be found in use around the world today (and a few of historical interest), together with the appropriate conversion factors needed to change them into a ‘standard’ unit in the SI system of units.
UCMP Glossary of Natural History Terms
A dictionary of terms dealing with biology and related subjects.
Glossary of Class Names of Organic Compounds and Reactive Intermediates Based on Structure
Glossary of class names and definitions of class names of related substances available through the International Union of Pure and Applied Chemistry.
Glossary of Terms used in Bioinorganic Chemistry available through the International Union of Pure and Applied Chemistry
This glossary contains definitions and explanatory notes for approximately 400 terms used in the multidisciplinary field of bioinorganic chemistry.
General
Webster’s Revised Unabridged Dictionary
Webster’s Revised Unabrided 1913 dictionary particularily useful for historical terminology.
Oxford English Dictionary
This dictionary contains the entire text of the 22-volume Oxford English Dictionary, second edition, includes information on a word's origins and its historical context through time.
Dictionary.com
Dictionary.com includes an English-language dictionary, a variety of foreign language dictionaries, Roget’s Thesaurus, and a translator.
A Web of On-Line Dictionaries
This Web site links more than 600 dictionaries in 150 different languages.
Glossarist
This Web site provides an index of over 4500 glossaries that have been organized into 130 categories.
Roget’s Thesaurus
Search the 1911 edition of Peter Roget’s thesaurus courtesy of Michael Hart and the great folks at Project Gutenburg.
Roget’s II: The New Thesaurus
This Web page consists of the Third edition of Roget’s II Thesaurus (1995). Includes a list of synonyms and links to broader antonym/synonym groups.