Apple Dictionary
Your Mac also comes with a versatile Dictionary application.
18 Alternatives To Apple Dictionary
Blueseal Dictionary
Comprehensive dictionary of English, German, Spanish and French including synonyms.
Cambridge Dictionaries Online
Cambridge University Press has been publishing dictionaries for learners of English since 1995.
Collins English Dictionary
The official Collins English Dictionary online.
Google
Google Search, also referred to as Google Web Search or simply Google, is a web search engine developed by Google. It is the most used search engine on the World Wide Web
Macmillian Dictionary and Thesaurus
The Free Online English Dictionary from Macmillan Publishers.
Merriam-Webster
No other dictionary matches M-W’s accuracy and scholarship in defining word meanings. Our pronunciation help, synonyms, usage and grammar tips set the standard.
Oxford Dictionaries
Free online dictionary of British English and American English from Oxford.
Power Thesaurus
Power Thesaurus is a fast, comprehensive and easy-to-follow online thesaurus for writers…
SayWhat
A fun and informative Video Urban Dictionary.
StarDict
StarDict is a Cross-Platform and international dictionary Software.
The Free Dictionary
The World’s most comprehensive free online dictionary, thesaurus, and encyclopedia with synonyms, definitions, idioms, abbreviations, and medical, financial, legal specialized dictionaries
The Online Slang Dictionary
Learn thousands of real slang words or add your own.
Wiktionary
Open Source wiki-dictionary by the Wikimedia foundation
WordReference
WordReference is a free online Oxford dictionaries for Spanish, French, Italian, German and more.
Wordnik
the biggest online English dictionary, by number of words