Nisus Thesaurus is a fast electronic thesaurus that automatically integrates with any service aware application including Nisus Writer Pro, Nisus Writer Express, Apple Mail, Safari, TextEdit, and more.

What’s New

Version 1.2

Added: Dark Mode.

Ratings and Reviews

3.3 out of 5
58 Ratings

58 Ratings

EternalPanda81 ,

Pretty limited...

This can't be your only thesaurus if you're interested in genuinely exploring the words behind a concept that's on the tip of your brain. A few common words have a nice range of suggestions, but it wasn't the kind of broad spectrum of esoteric associations implied in the picture for what I've tried so far.

Ex: "Critical = decisive, vital" … If either of those were helpful then it's seriously unlikely that a thesaurus is going to make the difference in polishing up whatever it is you're writing.

I wish I could be more specific, but I can't find the words. If only I had good thesaurus. :-/

mircrez ,

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!!!!!!

Bob Kerstetter ,

Extraordinarily Useful — But Than a Thesaurus

Nisus Thesaurus relates words by concept more than by equivalence. For example, Looking up "intelligent" provides pathways to words related to "reasoning," "thinking," and "well-informed," plus "healthy," "level-headed," and "sound," the final one being good judgement. The software benefits writers by suggesting alternative ways of viewing and understanding their research and ideas. If you just want different ways of saying things, you might consider the excellent Oxford dictionary and thesaurus built into Mac OS X. Nisus Thesaurus uses the WordNet database from Princeton University. It is an incredible tool for helping you create and refine your writing. Use it alongside a traditional more thesaurus to enrich your communication skills. In defense of Nisus, from a marketing point of view, calling it a thesaurus makes sense, but it is more than a synonym finder.


Nisus Software, Inc.
10.2 MB

OS X 10.11 or later, 64-bit processor



Age Rating
Infrequent/Mild Mature/Suggestive Themes
Infrequent/Mild Alcohol, Tobacco, or Drug Use or References
Infrequent/Mild Profanity or Crude Humor
Infrequent/Mild Medical/Treatment Information


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.