iDictionary is a Mac OS X application that allows you to create a custom dictionary and/or thesaurus for your iPod, and easily put it on your iPod. iDictionary leverages the built in dictionary available with OS X 10.4 along with some very smart filtering and optimization techniques to create a dictionary or thesaurus that will fit on an iPod. Although the dictionary/thesaurus is optimized to fit on your iPod it is still a fully featured dictionary containing most of the words (maybe more) a normal dictionary would have.