Yazi

Yazi is a dictionary program designed to assist users in their study and understanding of different Asian languages.

It has both a browse-able dictionary, and a lookup window where characters can dynamically be looked up using OS X services.
The program features: dictionary of most Chinese characters from Unicode with Chinese (Mandarin & Cantonese), Japanese, Korean and Vietnamese pronunciations; dictionary of Chinese words from CEDict; unicode/HTML conversion services and much more.