Chambers Dictionary is described as 'The single-volume international English dictionary with the widest coverage of all the riches of the English language. Clear, accurate and occasionally witty definitions, with the latest new words from science, technology and contemporary culture' and is a Dictionary in the Education & Reference category. There are more than 10 alternatives to Chambers Dictionary for a variety of platforms, including Online / Web-based, iPhone, Android, Mac and Chrome OS. The best alternative is Merriam-Webster, which is free. Other great apps like Chambers Dictionary are Dictionary.com (Free), The Free Dictionary (Freemium), Cambridge Dictionary (Free) and Thesaurus.com (Free).
Online Dictionary - Multiple dictionaries including: English dictionary, medical dictionary, legal dictionary, financial dictionary, computer dictionary, thesaurus, dictionary of acronyms and abbreviations, dictionary of idioms, thesaurus, Columbia encyclopedia, Wikipedia...
Free online dictionary of British English and American English from Oxford. Translate from English to Spanish, French, Italian, and German with bilingual dictionaries. Get writing, spelling and grammar help, and play word games. (US)
Advanced English Dictionary is better than other dictionaries, not just because it contains far more words than a conventional paper dictionary, but because it uses a radically new approach to searching for words.