- Cambridge Dictionaries Online
Designed for international or second-language speakers, this site provides searchable versions of Cambridge's Advanced Learner's Dictionary, Dictionary of American English, International Dictionary of Phrasal Verbs, International Dictionary of Idioms, and Learner's Dictionary.
- Century Dictionary
A complete searchable version of the first edition of the Dictionary and its supplements.
- Chambers 21st Century Dictionary and Chambers Thesaurus
Part of Chambers Reference Online, freely searchable versions of the dictionary and the 1996 edition of the thesaurus, as well as the 1997 edition of Chambers Biographical Dictionary.
- Glossarist: a Searchable Directory of Glossaries and Topical Dictionaries
May be searched by keyword or browsed by category.
- Merriam-Webster Online
Searchable versions of the Collegiate Dictionary and Collegiate Thesaurus with links between the term defined and its synonyms. Also includes a Spanish-English dictionary.
- Middle English Compendium[Rutgers Restricted]
Includes a searchable version of the Middle English Dictionary, a HyperBibliography of Middle English including all the works cited in the Dictionary, and A Corpus of Middle English Prose and Verse.
- OneLook Dictionary Search
A single search interface for an extensive collection of Web-based dictionaries covering art, business, computing, medicine, religion, science, slang, sports, technology, and a variety of other subject and general language resources including a reverse dictionary.
- Online Etymology Dictionary
Compiled from an extensive list of identified sources, the dictionary can be searched or browsed alphabetically. A list of the abbreviations used in the dictionary is included on the main page, and a search engine for the site is provided.
- Oxford English Dictionary [Rutgers Restricted]
A searchable and continuously updated version of the definitive English language dictionary on word origins and usage. Allows searching of the entire text of the dictionary including words used in the definitions, etymologies, and illustrative quotations; authors of quotations; and full phrases.
A searchable dictionary for finding words that rhyme. Results are broken down by number of syllables, and allow follow-up searching for definitions, synonyms, homophones, etc.
- Roget’s International Thesaurus of English Words and Phrases
A searchable online version of the book by the same name, with category and alphabetical indexes.
A simple search interface. Based on Roget's II: The New Thesaurus.
Links to dictionaries, encyclopedias, glossaries, and other electronic reference works in English or Spanish.
- Urban Dictionary
A user written dictionary of slang terms.
Provides verb conjugations for hundreds of languages, ranging from national and international languages to regional and even extinct languages. Includes English, French, Spanish, German, Chinese, and many more.
- Visual Dictionary Online
Search one of 15 themes to quickly locate words, or find the meaning of a word by viewing the image it represents.
- WordNet: a Lexical Database for the English Language
From the Cognitive Science Laboratory at Princeton University, a searchable English lexical database listing hyponyms, synonyms, coordinate terms, etc.
Includes a quick search option, plus links to hundreds of dictionaries in hundreds of languages; links to glossaries and dictionaries in many subjects; and links to translation and language-related resources on the Internet.