Cambridge Dictionary Online. (2011). Cambridge University Press. Retrieved October 6, 2011, from http://dictionary.cambridge.org/
From the respected, authoritative sources at Cambridge University Press, the Cambridge Dictionary Online provides American English, British English, student, and select bilingual editions. With its focus on contemporary definitions and usage for common words, phrases, and expressions, this dictionary is a good resource for learners of English as a second language and its linkage with a trial version of the ThinkMap Visual Thesaurus is particularly helpful in identifying related words and expressions. With its focus on common usage, this dictionary does not provide information on word history and also may not contain less common words that may be available in other robust dictionaries of the English language.
Dictionary.com. (2011). Dictionary.com, LLC. Retrieved October 6, 2011, from http://dictionary.reference.com/
A popular, free, easy-to-use online dictionary, dictionary.com licenses content from 15 authoritative sources including Random House and Harper Collins. Dictionary.com also provides text translations supporting over 50 languages, quotations, thesaurus, and word games. It's also a valuable source for improving vocabulary skills with its inclusion of word games for different age groups (elementary school, middle school, high school, and college age and beyond) and vocabulary preparation exercises for standardized tests such as the SAT and ACT.
Merriam-Webster Online. (2011). Merriam-Webster, Incorporated. Retrieved September 24, 2011, from http://www.merriam-webster.com
The Merriam-Webster Online Dictionary is a free, online dictionary based on the print version of Merriam-Webster's Collegiate® Dictionary, Eleventh Edition and is supported by the same trusted resources that have made Merriam-Webster a leading provider of information for over 150 years. The Merriam-Webster Online Dictionary also includes a Spanish-English dictionary, a medical dictionary, and an encyclopedia. It also provides fun features such as word games and word of the day.
Merriam-Webster's Word Central. (2011). Merriam-Webster, Incorporated. Retrieved October 6, 2011, from http://www.wordcentral.com/
Merriam-Webster's Word Central is a free online dictionary and thesaurus for the 11-14 year old age group. Word Central provides child-friendly definitions, rhyming words, buzz word of the day, and word games.
Oxford English Dictionary. (2011). Oxford University Press. Retrieved September 25, 2011, from http://www.oed.com.proxy-um.researchport.umd.edu/
Widely regarded as a top authority on the English language for over 150 years, the Oxford English Dictionary is regarded as the premier dictionary of the English language and word history. The focus on word origins and word history are what distinguishes this dictionary from many others. The online version is based on the Oxford English Dictionary 3rd edition and is updated quarterly. The Oxford Press does charge an annual subscription fee at the individual or institution level.
The Free Dictionary. (2011). Farlex, Inc. Retrieved October 6, 2011, from http://www.thefreedictionary.com/
The Free Dictionary claims to be the world's most comprehensive dictionary and provides dictionaries in 13 languages as well as medical, legal, and financial dictionaries, a thesaurus, acronyms and abbreviations, idioms, an encyclopedia, and a searchable literary reference library. The Free Dictionary is also loaded with features like "This Day in History", "Article of the Day", "Quotation of the Day" and multiple word games, The site provides results from a number of credible dictionaries such as American Heritage and Cambridge, but also may provide results from Wikipedia and other non-peered reviewed sites, so when using the site, care should be taken to review the information as to what dictionary or reference source is providing the definition.