Exhaustively researched and thoroughly revised, the Fifth Edition contains 10,000 new words and phrases, over 4,000 dazzling new full-color images, and authoritative, up-to-date guidance on usage. Thousands of definitions have been revised in rapidly changing fields such as astronomy and biology, geographical entries and maps have been completely updated, and the dictionary’s signature feature notes on word history, synonymy, and language variation have all been enhanced and improved. This is the perfect solution to use at school, in the office, or at home!

Word meanings are made easier to understand with thousands of new quotations from classic and contemporary writers. Etymologies explaining word origins and development have been newly created or revised to reflect the very latest scholarship. Many words are traced back to their roots in prehistory through two unique appendixes showing word roots in ancient Indo-European and Semitic.

Also includes advanced search and language tools that have become the staple of quality language apps from MobiSystems.

SEARCH TOOLS – effortlessly find words using a clear, functional, and easy-to-use interface. The integrated search tools activate automatically the moment you start typing:
* Search autocomplete helps find words quickly by displaying predictions as you type
* Keyword lookup allows you to search within compound words and phrases
* An automatic ‘Fuzzy filter’ to correct word spelling, as well as ‘Wild card’ ('*' or '?') to replace a letter or entire parts of a word
* Camera search automatically searches for words in the camera viewfinder and displays results

LEARNING TOOLS – engaging features that help you further enhance your vocabulary:
* ‘Favorites’ feature to create custom folders with lists of words from the extensive library
* ‘Recent’ list to help you easily review looked-up words
* ‘Word of the day’ section to help expand your vocabulary every day

*Thesaurus base with audio is available as an In-App Purchase *

Get Thesaurus to access the full capacity of the language app.
THE AMERICAN HERITAGE® ROGET'S THESAURUS offers an intelligent and sensible guide to synonym selection. It provides a wide range of synonyms, ranging from mainstream vocabulary to the colorful alternatives that make English such a rich and versatile language. Thousands of slang, informal, and regional words broaden the coverage even further. Each synonym list focuses on a clear definition that quickly orients the user to the relevant meaning.

If you have any questions, feedback or suggestions please contact us directly at

What's New

Version 10.0.5

• iOS 11 support!
• Complete visual redesign
• New Home view for quick access to the most frequently used functions
• Now Swipe to delete entries from the Favorites and Recent menus
• Navigate the Word of the Day entries by swiping
• Recently viewed entries will appear at the top of the search field
• Bug fixes

Ratings and Reviews

3.9 out of 5

31 Ratings

31 Ratings

Will let you see a fraction of the words in the actual dictionary


I have been a huge fan of AHD for a number of decades and downloaded this app, in hopes that it could offer features available in the print edition.
I do like the "Word of the day" feature, when it actually displays the word, but, as it is with the rest of this app, you will not often be able to see either the word or the definition. The app does not proceed to an actual definition when searching for a word; it will simply "suggest" the word it thinks you are wanting to see. There is no functionality beyond that.
This has been a very disappointing app, and especially to a devoted user of AHD, it is only a few steps above worthless. Very sad. I never wanted to consider a competitor's product, but may be forced to do so, including looking elsewhere for a desktop computer version. That product is well beyond worthless, and in fact can do literal damage to your computer (they offer downloads, but numerous disclaimers that protect them from liability, because their downloads are laden with viruses, which they acknowledge). Shame on you, producers of one of the best dictionaries of all time, for creating such poor products. I hope you will once again create a great dictionary, in an electronic version, but I have a distinct feeling that those days are gone.

Developer Response

Hello, WazeSir! We are sorry that you are disappointed with the dictionary. Please feel free to contact us at and share your recommendations about the app. Thank you!

Great dictionary, but a couple of UI omissions


I've long appreciated the scholarship that goes into the American Heritage Dictionary. The Usage Panel is a great way to examine the state of the language, though I do think it would be improved by the addition of some good corpus-based linguistics. Having that dictionary available on iOS devices is a great form factor and extremely convenient. (I'm also enough of a language geek to enjoy having the appendices containing Semitic and PIE roots -- fascinating reading!)

The app is generally pretty good, and offline access is great! There is, however, one really unfortunate omission, and this is the main thing preventing me from giving the app 5 stars. It's great to be able to browse the dictionary by tapping on words that appear in definitions--but it's really irritating not to have a "back" button! This is particularly true when I've jumped to another entry by mistake. (Swiping from the left just opens the menu, and I don't see an obvious control for this operation.)

Developer Response

Thank you for your detailed feedback. We are always trying to answer all users' requests. Please follow our next releases for updates. In the meanwhile, if you have any questions, please contact us directly at:

Five Star Review


You are very far from five stars. You are nothing more than a desk top dictionary. You forget that you are competing with google and the free dictionary by Farlex. If I can’t spell a word correctly you are no help. Your history and usage of words is skimpy. You make me pay an exorbitant fee periodically to continue to use your app. You are slow sometimes and your request for a five star review every time I open your ap is annoying. Remember I paid as much to use your app as to purchase a hard bound dictionary. For the price I expected a fairly extensive history of words


MobiSystems, Inc.
34.5 MB
Requires iOS 9.0 or later. Compatible with iPhone, iPad, and iPod touch.
English, Catalan
Age Rating
Rated 4+
© 2017 MobiSystems, Inc.
In-App Purchases
  1. American Heritage English Dictionary + $4.99


  • Family Sharing

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

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