http://www.peevish.co.uk/slang/ A Dictionary of Slang: English slang and colloquialisms used in the United Kingdom
http://www.rootsweb.com/~genepool/sayings.htm A dictionary on the origins of some commonly used old English sayings.
http://www.artsci.wustl.edu/~philos/MindDict/ A searchable database of peer-reviewed articles on concepts and individuals in the philosophy of mind. Category: Dictionaries
http://www.allwords.com/ AllWord.com: Search words, hear pronunciation, see English meanings and translations.Category: Dictionaries
Business Related http://www.alphadictionary.com Alphadictionary.com: Free online English dictionary, dictionaries and grammars for 300 languages and more than 120 subject-specific dictionary sites (under Specialty Dictionaries), crossword puzzles, word games, language jokes, and a Word of the Day by a world-renowned linguist. Includes podcasts, a forum and a blog.
http://www.answers.com/ Answers.com: Answer engine, with talking dictionary, thesaurus, encyclopedia, bios, tech terms, news, sports, weather, and much more.Category: Dictionaries
http://www.askoxford.com/ AskOxford.com: The Online Oxford Dictionary.
Contains a dictionary and thesaurus, as well as quotations, word of the day, games, and lexicography.Category: Dictionaries
http://www.travel-library.com/asia_pacific/australia/au_2005... Australian English Glossary from A to Zed: A glossary of Australian English.
By David StybrCategory: Dictionaries
Business Related http://www.bartleby.com/61/ Bartleby. com: Dictionary: The American Heritage Dictionary of the English Language.
Over 90,000 entries feature 10,000 new words and senses, 70,000 audio word pronunciations, 900 full-page color illustrations, language notes and word-root appendixes.Category: Dictionaries