Google Dictionary

Google's dictionary extension on Google Chrome. With it, you can double-click any word to view its definition in a small pop-up bubble, or search the complete definition of any word or phrase using the address bar dictionary.

Free Chrome OS Chrome

WordReference

WordReference is a free online Oxford dictionaries for Spanish, French, Italian, German and more. Conjugations, audio pronunciations and forums for your questions.

Freemium Android iPhone Web

Apple Dictionary

Your Mac also comes with a versatile Dictionary application. It also includes to other reference libraries such as thesaurus, Apple glossary, and Wikipedia.

Free Personal Mac OS X

Blueseal Dictionary

Comprehensive dictionary of English, German, Spanish and French including synonyms.

Free Mac OS X Windows Linux Android iPhone Chrome OS Web Blackberry

Glosbe

Huge collaborative massively multilingual dictionary.

Free Personal Web

Visuwords

The fun and free way to look up definitions. THE graphical dictionary and visual thesaurus. We love words.

Free Web

Allkdic

Handy status bar dictionary.

Free Mac