AllWords.com - Features two modern English dictionaries, multilingual search, and translation. Also features a guide to language sites on the web and a language discussion forum.
Alphadictionary - Search 992 Online English Dictionaries at Once!
AskOxford.com Searchable online version of the Compact Oxford English Dictionary, as well as thesauri, quotations, foreign language dictionaries, a word of the day, and games.
British National Corpus (BNC) - a 100 million word collection of samples of written and spoken language from a wide range of sources, designed to represent a wide cross-section of current British English.
Cooldictionary.com - Free edition of a complete Webster dictionary. Fully crosslinked
Collins Word Exchange - Online dictionary and word tools from Harper Collins. Search word definitions and thesaurus entries, submit a new word to the dictionary, or try out the Scrabble word checker, crossword solver, or texting abbreviation tools.
definr - Very fast and simple dictionary which suggests possible words as you type. Good for the spelling-challenged
DICT.org - Dictionary search site that draws on dictionaries and reference sources including Webster's, Jargon File, translation dictionaries, and Roget's Thesaurus. Created as part of an experiment to create a data exchange protocol for dictionary information
Encarta World English Dictionary - Online English dictionary and thesaurus, featuring audio clips of words pronounced, as well as a word of the day
eLook Dictionary - Provides definitions, synonyms, and related words
EZresearch.com - Provides a directory of dictionaries
Free Dictionary, The - Free online dictionary search, offering English, medical, legal, and computer dictionaries as well as a thesaurus, encyclopedia, and literature reference library
Heinle's Newbury House Online Dictionary of American English - Search over 40,000 entries to get clear concise definitions and when available related pictures
Hutchinson Dictionary of Difficult Words - Search or browse this dictionary of more than 13,000 words
Hutchinson Dictionary of English - Defines selected words that are often misused or misspelled. The Hutchinson Dictionary of English Usage explains the difference between words that are commonly misused
HyperDictionary.com - Online dictionary featuring links to explanations of difficult terms within a given word's definition. Includes a thesaurus and searchable dictionaries for English, computers, dreams and medicine
Hypertext Webster Gateway - WWW interface to multiple English dictionaries
Information Please Dictionary - Infoplease's free online dictionary. Features almanacs, an encyclopedia, and an atlas
iTools Language Tools - Online dictionary service that includes a thesaurus, industry-specific terminology, crossword puzzle and Scrabble help, and translation tools
Longman Dictionary of Contemporary English - Online English dictionary, with photo illustrations, audio files of selected word pronunciations, example sentences, and lesson plans for teachers. Also available as a CD-ROM edition
LookWAYup - Online multilingual dictionary and thesaurus search tool
KnowPlay? - Simple and integrated access to dictionaries, thesauri, encylopedias, and quotation databases
Merriam-Webster Dictionary - Free online version of the Merriam-Webster English dictionary, with searchable dictionary definitions, thesaurus, and a student dictionary for kids
Merriam-Webster OnLine - A free, searchable on-line dictionary and thesaurus, word games, a word of the day, and many other English language and vocabulary reference tools and resources
Merriam-Webster's Word Central - Offers kids a student dictionary, Word of the Day, and interactive word games. Includes homework help and lesson plans for parents and teachers
ObjectGraph Dictionary - Free online dictionary that suggests words and phrases as you type in the search box
OneLook Reverse Dictionary - Reverse dictionary lets you enter a concept to see matching words and phrases, for those times when you remember the definition but not the word
Oxford Advanced Learner's Dictionary - Allows users to search, free of charge, for entries in the latest (year 2000) edition of the Oxford Advanced Learner's Dictionary
Planet Translation - Directory of dictionaries, including unilingual, multilingual, and topical resources
The Glossarist - Searchable directory of glossaries and topical dictionaries containing terms and definitions on hundreds of subjects
Visual Dictionary, The - See definitions for terms from biology, anatomy, and music with the InfoVisual visual dictionary. Browse by topics and thumbnails, or search for a word or phrase
Webster's Dictionary 1913 Edition - The 1913 edition of Webster's famous dictionary of American English
Webster's Online Dictionary: The Rosetta Edition - This database doubled with a metasearch tool extracts records from a variety of online and public-domain paper dictionaries, both general and specialized. It offers English definitions, as well as translations from/to a hundred languages
Word Assault - Looks up multiple words simultaneously using several databases including Webster's, Easton's, Wordnet, and the Devil's Dictionary
Wordsmyth: The Educational Dictionary-Thesaurus -WEDT touts itself as "the premier online American English dictionary with an integrated thesaurus." WEDT contains 50,000 headwords and well-defined and hyperlinked synonyms
WordWeb - A free English thesaurus and dictionary for Windows
WordWeb Online - Online dictionary and thesaurus which covers American, British, Australian, Canadian, and Asian English spellings and words