Adding Dictionaries to Dictionary.app

As of OS X 10.8.2, Dictionary.app has modules for reference dictionaries in US English, British English, French, German, Spanish, Japanese, and Simplified Chinese. Some ways to add more are :

This site has German, Arabic, Latin, Chinese, Italian.

Etresoft has a dictionary for the Quran and two Bible dictionaries.

Others available are Italian, Norwegian, Catalan, and Romanian.

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