Dictionaries and glossaries

General monolingual dictionaries
General multilingual dictionaries
Synonym dictionaries
Specialized dictionaries and glossaries

Acronyms
Computing
Internet
Science
Medicine
Financial
Technology
Humanities
Social Sciences
Sports
Food and drink
Art and music
Various

General dictionaries

• Hypertext Webster Interface. Search mode. Definitions and contexts, and most of the words in definitions are also hiperlinks. It includes thesaurus information and the words in other languages.
• Merrian-Webster's Collegiate Dictionary. Dictionary and thesaurus.
• Dictionary.com. It also includes a grammar section, a browser, etc.
• OneLook Dictionaries. Looks up the word in 105 general and specialized dictionaries (almost 650,000 entries). Search can be restricted to some dictionaries.
• Encyclopedia.com. Over 14,000 articles with information on almost any topic.
• Oxford English Dictionary. By subscription.
• BritSpeak. British and American English. Browser. It has a list of false friends and links to other pages (BritLinks) and English dictionaries.
• Casey's Snow Day's Reverse Dictionary. It finds the word that matches a given definition. Thesaurus information and definitios are from the Webster Interface. It doesn't work very well, but gives amusing alternatives.
• On-line Rhyming Dictionary. Definitions from the Webster.
• Oxford Slang Dictionary. By subscription.
• A Glossary of Hardboiled Slang.

Portuguese

• Universal Dictionary. Information about pronunciation, gramatical cathegory and etymology. Related words and verb conjugation. Links to more dictionaries.
• Dicionário da Porto Editora. Over 600,000 entries, with expressions, etymological information, etc. It also includes bilingual dictionaries in English and French.

Spanish

• Diccionario Anaya de la Lengua. 33,000 entries. With idioms, synonyms and lexical families. It includes a Spanish-English-Spanish dictionary.
• Diccionario Vox de la Lengua Española.
• Dictionary of synonyms and antonyms. Prepared by the University of Oviedo. Definitions in English and Spanish.
• Diccionario Americano. Words and expressions used in the different Latin American countries. It includes synonyms.
• Spanish language's Jargons. Typical expressions of Spanish speaking countries.
• Dictionary of Spanish Jargons.

German

• Meyers Lexikon. Monolingual on-line dictionary. It just allows three users at a time, so you may have to wait.

Catalan

• Diccionari de la llengua catalana. Prepared by the Institut d'Estudis Catalans.

Multilingual

• EURODICAUTOM. Both source and target languages are: Danish, Dutch, English, Finnish, French, German, Greek, Italian, Latin, Portuguese, Spanish and Swedish. Mainly official and technical terms. It has additional information such as idioms, phraseology, abbreviations, definitions, etc.
• Michaelis Dictionaries. You must register, but it is free. From Portuguese to English, Spanish, French, Italian and German, and vice-versa. It has a link to Universo Online, a Brazilian server.
• LOGOS on-line dictionary. Multilingual dictionary that inludes over thirty languages and more than 5 million entries. Maintained by a team of translators, but new entries can be suggested. Appart from the dictionary, it has links to specialized magazines, a text corpus, etc. LOGOS is a translation agency and in its home page there is some information about the sevices it offers.
• French-English-French Dictionary. Some 75,000 entries. From the ARTFL Project of the University of Chicago.
• DICOVOX. French-English-French and German-English dictionary. Quite complete and with idiomatic expressions. Besides, it has English pronunciation.
• LEO Dictionary. German-English-German. Over 130,000 entries. It includes idioms and gives the possibility of solving problems.
• German-English-German Diccionary. 100,000 entries. Search mode.
• The New English-German Dictionary. Searchable in both directions. It also includes some grammar notes.
• WordReference.com English-Spanish-English dictionary and translator.
• English-Basque Dictionary. Word list from English to Basque.
• English-Russian-English Dictionary.
• The Alternative Dictionaries. Multilingual dictionary of bad language and other words not easily found in a conventional dictionary. More than 70 languages, with a variable number of entries contributed by users.
• Esperanto-English  / English-Esperanto dictionary. Search mode.
• Esperanto-German  /  German-Esperanto Dictionary.
• Freedict.com. List of bilingual dictionaries including English and other languages.
• Freelang. Several bilingual dictionaries to download to and from French and other languages.

Synonym Dictionaries

• WordNet. Synonyms and related words.
• WordNet 1.5. Dictionary of synonyms, antonyms, related words and information about word usage. The difference between this and the previous one is that here you can choose what you want to look up.

Specialized dictionaries and glossaries

• Acronym Dictionary. Very complete.
• Abbreviation and acronym dictionary. In English.
• List of Acronyms. Text mode.

• FOLDOC: Free On-line Dictionary of Computing. In English. Very complete. It includes abbreviations, jargon, programming languages, firms, people, some humorous entries, etc. It also has some interesting links. A text copy can be downladed here to work off-line.
• Dictionary of Computing. Galician-English-Spanish. Prepared by Xavier Gómez Guinovart and Anxo Lorenzo.
• Webopedia. On-line dictionary and search engine.
• Hacker's Jargon. English or German interface. Colloquial definitions.
• Software Engeneering Glossary. Search mode. Links to additional information in some terms.
• Microsoft Glossaries. ftp files. Computing glossaries in several languages.
• English-Russian Dictionary of Computing Abbreviations.
• Panlatin dictionary of computing terms. In English, Catalan, Spanish, French, Italian, Portuguese and Romanian. Definitions are in French.

• Dictionary of Internet terms. Galician-English-Spanish-Portuguese, with Galician definitions. Prepared by Ana Hermida.
• Trilingual Internet Glossary. In English, French and Spanish.
• Dicionário do Internetês. In Portuguese.
• NETGLOS. Multilingual glossary of Internet terms. It has a list of Internet tutorials and glossaries in several languages.
• Internet terminology. In English and French.
• ILC Glossary. (Internet Literacy Consultants). English glossary of Internet terms.
• Commando. German Internet glossary.
• L'ABC des réseaux. French glossary of Internet terms. English words with French translation and definition.
• INTERDIC. Spanish technical Internet dictionary. It also includes some interesting articles and links.
• InterDiccionari. In Catenglish. Catalan definitions.
• Basic Glossary English-Spanish for Internet users. Published by ATI (Asociación de Técnicos de Informática).
• The Internet Dictionary Project. English, French, Spanish, Portuguese, German and Italian. Not many entries so far.
• Acronym and Smilely Dictionary. Dictionary of common abbreviations and emoticons.

• Dictionary of Cell Biology. Prepared by the University of Glasgow.
• FINS glossary. Aquarium-related terms English glossary. In the main page there are fish listings with the scientific name and more information on that subject.
• Birdwatcher's Dictionary. Topics are listed alphabetically and you may also search for a specific term.
• Dictionary of rabbit keeping. In Spanish. Very comprehensive and with many related terms.
• PlantWorld. Collection of glossaries on Botany, horticulture and gardening.
• Botany online. German-English-German glossary.
• Plant Encyclopedia.
• Glossary of Roots of Botanical Names. Most of roots coming from Latin. Explanations in English and one example of each one.
• Agrovoc. The FAO's Agricultural Thesaurus, in English, Portuguese, French and Spanish.
• Glossary of Australian flora.
• Biology: Dictionaries and Glossaries.
• Terms of Environment. In English.
• Compendium of Environmental Acronyms AEG. (Association of Engeneering Geologists). Environment-related abbreviations.
• Glossary of Forestry Terms. In English.
• Environment glossaries. In English and French.
• Interactive chemical dictionary. In Portuguese.
• German-English-German dictionary of Organic Chemistry. About 2100 entries. No definitions.
• WebElements. The periodical table of elements with translations into French, Spanish, German and Italian and English pronunciation.
• Gems and Precious Stones. Terms on gemology, mineralogy and geology with diagrams and images.
• Astronomy Thesaurus. English, French, German, Italian and Spanish. Without definitions, but it gives related and general terms and the correspondence in the other languages. Sunrise Sunset Glossary. English and Spanish Astronomy glossary.

• Glossary of medical terms. Multilingual glossary on medical terms, both scientific and colloquial, in eight European languages: English, French, Portuguese, Spanish, Danish, Dutch, German and Italian.
• The On-Line Medical Dictionary. It includes terms relating to biochemistry, cell biology, medicine, molecular biology, physics, science, technology, etc. Over 16,000 definitions.
• Roche Lexicon. Medical dictionary with German terms and definitions and their English correspondents.
• IDC-9: Index of Diseases. There is a tabular list and an alphabetical index.
• Glossary of Ophthalmology. In Spanish.
• Genetics Glossary. In Spanish.
• HIV-AIDS Glossary. In Spanish. It includes a glossary of medicaments.
• The Expanded Dictionary of Metaphysical Healthcare. Alternative medicine, paranormal healing and related methods.
• Dictionary of Virology.
• Glossary of Terms for Eye Care. In English.
• Omni. It includes a searching machine where you can find a good number of glossaries on Medicine and Engineering, apart from other biomedical information.

• TermFinance. On-line dictionary of business terms in English, French, German and Italian. With related terms.
• Glossary of actuaries and insurance. English-French.
• The Complete Glossary of Insurance Coverage Explanations. In English.
• Glossary of economic terms. >From the government of Canada. It also has a French version.
• NYSE Glossary. English glossary of financial terms.
• Equity Analytics, Ltd. Several financial glossaries.
• Foreign Trade Multilingual Glossary. English-Spanish-Portuguese-French.
• Accounting Glossary.
• Financial Glossaries. A quite comprehensive list classified by subject.
• Financial Dictionary. In Spanish.
• La Bolsa de Joramón. Spanish dictionary of stock-exchange terms.
• Glossary of the euro. >From the European Comission. Terms in French, Italian, Dutch, Portuguese, Spanish, Danish, German, English, Finnish, Greek and Swedish.
• Campbell R. Harvey's Hypertextual Finance Glossary.
• The washingtonpost.com Business Glossary.
• Money Words. Searchable and browsable financial glossary.

• NASA Thesaurus. Scientific and technological terms. Very complete. No definitions.
• Glossary of Telecommunication Terms. Very complete. In English.
• Technical glossary on Computing, Electronics and Telecommunication. English-Spanish.
• Termite. Telecommunication glossary in French, English, Spanish and Russian. No definitions.
• Radar Meteorology Glossary In English.
• Batteries from A to Z. Everything you've always wanted to know about batteries but you've never dared to ask. 300 terms in English and German.
• Energy glossary. In English. From the Access Energy page of the California Energy Commission, where you can find more information.
• HydroCut glossary. Explosive-related terms.
• Des mots et des autos. French glossary of car-related terms. Some synonyms and English equivalents.
• Aircraft. In English.
• Bicycle Glossary. Quite comprehensive English resource.
• Soaring Glossary. English-German-English.
• The Sun's Joules. Glossary of ecological energies. English definitions and terms in English, French and Spanish.
• Tecnoguía de MCI. A complete glossary in Spanish and English with definitions and usage of 1000 terms related to computing and technology.
• Comparative CyberLexicon. English-Spanish dictionary of technology.
• Whatis. Dictionary of information technology. You can browse or search for a term or by topic. Diccionario de tecnoloxías da información en inglés. Pódese consultar alfabeticamente ou por temas.

• Glossary of Rhetorical Terms. With examples and more links.
• The Encyclopedia Mythica. An encyclopedia on mythology, folklore and legend. Both searchable and browsable.
• Russian-German Glossary of Linguistic Terminoloy.

• HASSET electronic Thesaurus of Humanities and Social Sciences. Based on the UNESCO thesaurus.
• WWLIA dictionary. Dictionary of legal terms in English with simple definitions. It has links to other pages about Law.
• Glossary of European Communities and European Union. Acronyms, politics, institutions, programs and other terms. In English.
• Glossary of institutions, policies and enlargemente of the European Union. All the members' languages.
• Glossary of Women and Development. English-French-English. Prepared for the IV World Conference on Woman, celebrated in Beijing. 850 terms and expressions on woman integration, education, health, violence, human rights, economy, politics, equality of sexes and environment.
• Hypertext Medieval Glossary. With book references.
• Dictionary of Feudal Terms. Especially English Feudalism. Text mode.

• Climbing dictionary. Terms in English, German, French, Dutch, Spanish, Italian... and definitions in English. Text mode.
• Fencing dictionary. In French.
• Golf terminology. In French.
• Chess Dictionary. Russian-English.
• Sports Glossaries. In English. Soccer, ice hockey, football and basketball.

• French-English dictionary of gastronomy.
• Dictionary of Spanish wine.
• Food Lover's Glossary. Multilingual terms with English definitions.
• Dairy Glossary. English-French-Spanish.
• Gastronomic Glossary. French-Swedish-English.
• Gourmet World. A list of glossaries on cookery, food and wine.
• Culinary Dictionaries and Glossaries.

• Online Film Dictionary. A multilingual dictionary which you can browse by cathegories or search for a specific term.
• Music Glossary. You can look up a specific term or choose a topic: instruments, composition, dancing...
• Words of Art. A glossary of art-related terms. It is still under construction.
• A Glossary of Photographic Terms

• Audiovisual Glossary. Portuguese-English-French. It includes some definitions.
• Technical dictionary of textile industry. French, English, German, Spanish. More than 10,000 terms about materials, industrial processes, etc. No definitions.
• Microglossaires de Termisti. >From French to other languages. Brief glossaries about various subjects: optic fibre, autism, microeconomy, etc. Definitions, contexts, related words, synonyms, etc.
• The Devil's Dictionary. English dictionary, with terms of different kind, mainly about religion and mithology.
• Dictionary of descriptive terminology on bookbinding and book keeping. In English.
• Tipography glossary. In English.
• Boating Basics Glossary of Terms. English glossary of nautical terms. This one seems more complete than the previous one, but both are brief.
• Virtual dictionary of Greco-Roman mythology. In Portuguese.
• Glossary of religious terms. In English.
• Glossary of slang drug-related terms. In English.
• Street terms: Drugs and the Drug Trade. In English. Organized alphabetically, by type of drug and by topic.
• Philatelic dictionary. Portuguese-English-French-Spanish. Click on Menu.
• Biographical dictionary. Information on over 18,000 people from the ancient times to the present day.
• Dictionary of Military Terms.
• Das Schuh- Und Lederlexikon. Monolingual glossary on leather products.
• Multilingual Real Estate Dictionary. German, English, French, Italian and Spanish.
• Do it yourself. German monolingual glossary.
• Labor Health Glossary. English-Spanish.
• Glossary of Construction Terms. In English. Terms are organized by sections.
• Dictionary of Laundry Terms. A really comprehensive English dictionary.
• Archaeology-related Glossaries.
• The Skeptic's Dictionary. Over 338 skeptical definitions, essays and references from abracadabra to zombis. It has a Portuguese version.
• Medialink Broadcasting Glossary.

Links to more dictionaries

• Yourdictionary. Dictionary search engine.
• Dictionaries on the WWW. List of dictionaries and glossaries.
• Dictionary list.
• Dictionaries. List of dictionaries and glossaries, especially English ones. You can see it with or without frames.
• Pedro's dictionaries. Dictionary list in 18 languages.
• Electronic Dictionaries. Collection of dictionaries and glossaries, classified by language and by subject. In the Terminological Forum page, for everyone interested in the terminological research. In English.
• Dictionaries and translators. Exhaustive listing of dictionaries and translation sevices.
• Martindale's 'The Reference Desk'. List of dictionaries and encyclopedias classified by subject.
• Dictionaries. Monolingual, multilingual, etc. From the Swiss Federal Administration's Central Language Services.
• OneLook Dictionaries. Classified by subject.
• Glossaries URLs. A comprehensive list of glossaries sorted by topic.
• Dicsearch. A searchable database with online dictionaries and glossaries in several languages.