This tool allows lookup and retrieval of WordNet data based on the user-supplied search word.
[1] The "Official" WordNet project site describes the original project and development of its resultant data source, called on by this interface, in detail.
I have created additional interfaces to the WordNet data here
Also, if localization (sourcing the dictionary content to your locale specific language) into languages other than English ie French and if sourcing that translation from wiktionary/wiktionnairre is your thing, Yves Bourque's API to do that is at igrec.ca