I've been evaluating the English dictionary from SlovoEd (www.palm-dictionaries.com
). It is based on WordNet I believe but arranges the information very nicely. You get synonyms, antonyms, similar words, hypernyms, etc.
Just one annoyance that maybe someone has been able to overcome. When you launch the app, it immediately does a search for the last word that's in the edit field. Since I've got the dictionary database on my MS, this costs a number of seconds before I can enter the new word. I've tried erasing the edit field before leaving, but the last word is still used.
I've contacted their support people who said that it's the way it works. Not too helpful, but at least they responded quickly.
It does not do the automatic lookup when you use it from another application. In that case, it waits until you tap the word.