- The American-British British-American Dictionary - for English speaking people - by Jeremy Smith.
- A Basic Dictionary of American Sign Language (ASL) terms
- Brewer's Dictionary of Phrase and Fable - 1898 edition - over 18,000 entries that reveal the etymologies, trace the origins and otherwise catalog “words with a tale to tell.” From Bartleby.com
- Cambridge Dictionary (from Cambridge University Press).
- Dictionary.com
- Duhaime's Law Dictionary - recommended research resource for law students by both Cambridge and Oxford's law schools.
- Free Online Dictionary of Computing (FOLDOC)
- Hypertext Webster Gateway - this hypertext Webster interface provides a point-and-click client interface (for non-linemode browsers) for accessing various dictionary services on the Internet created by Bennet Yee.
- LOGOS Multilingual E-Translation Portal
- Merriam-Webster Dictionary
- NetLingo - The Internet Dictionary
- The New Hacker's Dictionary - slang, jargon and techspeak
- OneLook Dictionary - a search engine for words and phrases: the OneLook® search engine indexes more than 19 million words in more than 1000 online dictionaries.
- OnMusic Dictionary - music dictionary created by Connect for Education, Inc.
- RhymeZone Rhyming Dictionary - find rhymes, synonyms, adjectives, and more!
- Ultralingua Online Dictionary - (dictionaries in English, French, German, Italian, Portuguese, Latin and Spanish)
- WordNet Search - a large lexical database of English. Nouns, verbs, adjectives and adverbs are grouped into sets of cognitive synonyms (synsets), each expressing a distinct concept.
- Wordsmith - home of A Word a Day, the Internet Anagram Server, and the Wordster
- Wordsmyth- the premier educational dictionary-thesaurus.
