Can’t beat free, use Mac’s Services menu choice to access
After you install Nisus Thesaurus you have to figure out how to access it! In most Mac Apps simply selecting the text and right clicking on it and choosing “Services” > “Look up selection in Thesaurus” to access. You can also access under the apps name in the menu bar, and select services to see the same thing. If you love working with words then this is a great app! It really has some cool filtering not found in Chambers Thesaurus or SynMap. Thanks Nisus!
best choice for non-native speakers
Nisus Thesaurus has several features that make it the best choice for non-native speakers. The old-fashioned style of thesaurus is not very helpful for English learners because they typically don't know the meaning of the suggested synonyms and so end up choosing a word that doesn't make sense for their particular context. Nisus Thesaurus, on the other hand, provides a list of possible meanings for the word you look up, and then makes it clear which synonyms are appropriate for which definition. Even better, it lets you choose 'more specific' or 'more general' synonyms, so a non-native speaker can avoid choosing a word with an overly narrow meaning. I have recommended this thesaurus to my international students, but I was disappointed to discover that they can't use it on their smartphones. Please make this thesaurus available as an app for iPhone and iPad!!!!!!
Some words seem to have their entries fully in place, but others are nearly blank. I looked up “protective” and the only word that came up was the antonym “unprotective.” What about sheltering, sheilding, guarding… etc? It’s almost as if some of the entries are unfinished or deleted.
A simple interface that allows you to explore more specific and general word alternatives. This is the best thesaurus I've ever used.