Mobile phones have become really for downloading data, finding out geographical information, and finding out how to spell or translate a word. Most phones don't come equipped with a dictionary, but you can download one for free.
This walkthrough will teach you how to download and install JLearnItMe, a dictionary software that supports over 15 languages. It is supported by all mobile phones that run java applications.
Download and Install a Free Mobile Dictionary
For more information about this application, refer to this page. There, you can find the download links and installation guides for various brands and models.