Is there any way to change the dictionary used in iBooks? When reading books written in a non-English language I would like to have access to the dictionary function in the book's language (not translation, just dictionary lookup). Currently I'm reading Don Quijote in Spanish, and it would be really helpful to be able to lookup unfamiliar words.
This has changed in iOS7. Look up a word, at the definition UI push "Manage" in the bottom left, and a list of foreign dictionaries comes up:
English, Apple, Oxford-EN, Spanish, Korean, KOR-EN, JP-EN, Italian, German, French, Dutch, Simplified CN, SCN-EN, and Japanese.
Any & all can be downloaded from inside this "Manage" screen, and the definitions will trail (as things do on the OSX side with Dictionary.app).