Thesaurus Rex by

Common Sense Media says

Expand and explore vocab with pretty good word-finder.






What parents need to know

Ease of play

A video tutorial shows kids how to search for words and access many of the other unique features.


Kids can look up violent words to find synonyms.


Kids can look up sexual words and other words related to inappropriate content to find synonyms.


Curious kids may be motivated to type in curse words and other inappropriate language to find synonyms. These words are labeled with exclamation points in search results, but can still be viewed.


The app does promote and other word apps offered through the publisher.

Drinking, drugs, & smoking

Curious kids may look up synonyms for words related to drinking, drugs, and smoking.

Privacy & safety

Some icons direct users outside of the app to other content and apps, including a link to a YouTube tutorial. Their privacy policy states that user info, including e-mail address, is protected if the user is under 13.

Parents Need to Know

Parents need to know that Thesaurus Rex is an app that provides kids with a way to find the most relevant synonyms and rhymes to help improve their writing. It has a pretty academic vibe, lacking flashy graphics and sound effects, but the app's simple design gives kids what they're looking for quickly and painlessly. Kids hoping to jazz up their writing will make repeat visits as they try to replace tired words with more engaging synonyms, whereas others may need more coaxing to see the app's benefits.

What kids can learn


Language & Reading

  • spelling
  • vocabulary
  • writing



  • conveying messages effectively
  • speaking

Engagement, Approach, Support


No flashy graphics or sound effects here; it's focused solely on helping kids find the perfect words for their writing.

Learning Approach

Search results sort words by relevance, word length, and complexity. Words come accompanied by their definitions and audio pronunciations.


A YouTube tutorial highlights the app's features. Upgrades allow kids to search by syllable count and rhyming words, as well as see examples and tips.

What kids can learn


Language & Reading

  • spelling
  • vocabulary
  • writing



  • conveying messages effectively
  • speaking

Kids can learn more about words and spice up their writing as they search for synonyms to replace tired adjectives and non-descriptive nouns. The app discourages kids from simply picking the first synonyms they see by encouraging them to narrow their results and pay attention to the relevance of the words. It also helps them make those words a regular part of their writing by saving popular searches and marking their favorite new words. This digital tool definitely trumps a traditional thesaurus, but some of the best features require in-app purchases.

This Learning Rating review was written by Stacy Zeiger

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What's it about?

Just as with a regular thesaurus, kids look up a particular word with THESAURUS REX and receive a list of synonyms. Unlike with a regular thesaurus, however, the synonyms come organized by relevance. If seeing words sorted by relevance isn't enough, kids also can narrow their search results by word length and complexity. As kids skim the lists of words, they can see a short definition for each and hear an audio pronunciation. In-app purchases unlock additional features, allowing kids to use the app to find rhyming words and sort words by syllable count or see examples of words used in sentences. When they find words they like, they can save them for quick reference later.

Is it any good?


No matter what kids are writing, Thesaurus Rex can help kids improve their vocabulary. The app encourages kids to think beyond simply adding a few big words to their writing and encourages them to choose words that fit the overall tone and meaning of a story, essay, or sentence. The short definitions that accompany the words help kids quickly determine whether the synonyms will fit, as do the examples available through the Examples & Tips upgrade. It also one-ups the old-school thesaurus by providing modern expressions and slang words. It's not all that exciting design-wise, which may help kids focus on the words themselves, but some kids may want a bit more oomph. 

Families can talk about...

  • Families can talk about words. Why say "tabby" when "cat" will do? When is it important to find the perfect word? 

  • Have kids focus on specific word choices when reading a favorite book aloud. 

App details

Devices:iPhone, iPod Touch, iPad
Release date:November 4, 2013
Size:37.40 MB, LLC
Minimum software requirements:iOS 5.0 or later

This review of Thesaurus Rex by was written by

About our rating system

  • ON: Content is age-appropriate for kids this age.
  • PAUSE: Know your child; some content may not be right for some kids.
  • OFF: Not age-appropriate for kids this age.
  • NOT FOR KIDS: Not appropriate for kids of any age.

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Our star rating assesses the media's overall quality.

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Learning ratings

  • Best: Really engaging, great learning approach.
  • Very Good: Engaging, good learning approach.
  • Good: Pretty engaging, good learning approach.
  • Fair: Somewhat engaging, okay learning approach.
  • Not for Learning: Not recommended for learning.
  • Not for Kids: Not age-appropriate for kids; not recommended for learning.

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