Nisus Software, Inc. has released a beta version of Nisus Thesaurus. Nisus Thesaurus is a utility designed for matching words of similar definition. The app features support for Safari, Mail, and of course, Nisus Writer. According to Nisus Software:
Nisus Software announces the public beta release of its latest product, Nisus Thesaurus.
With Nisus Thesaurus you get a fast electronic thesaurus that automatically integrates with any Service aware application including Nisus Writer Express, Mail, TextEdit, Safari, and more.
Nisus Thesaurus is based on the WordNet lexical database. Features include a 120,000 word database, easy to use Cocoa based interface, integration with any services enabled application, built-in glossary, offensive words filter and more.
You can find more information about the Nisus Thesaurus beta release at the Nisus Web site. Nisus Thesaurus beta is currently available for as a free download.