Word Reference [ http://www.wordreference.com/ ]
Features free online Oxford dictionaries - Spanish, French, Italian, German and more. Includes conjugations, audio pronunciations and forums.

Your Dictionary [ http://www.yourdictionary.com/ ]
A free online dictionary that offers definition search from Webster's dictionary for word meanings and thesaurus. Find legal dictionary, technical words, glossary, foreign language translation, medical dictionary, and rhyming dictionary lists.