Terminology is a browser for the English language – part dictionary, part thesaurus and part research tool. Terminology makes it easy to explore words and phrases, diving down to more and less specific terms - accessing the web and other apps for more detail and sharing.

More than a dictionary, Terminology can be extended with custom actions to search the Internet and other reference apps – making it a great place to start all your searches.

Use the share extension to select text anywhere, in any app, and look it up in Terminology.

### Dictionary, Thesaurus & Search

- Offline U.S. English dictionary and word reference with simple clear definitions.
- Definitions, synonyms, antonyms and deeper word relations such as: more and less specific words, part, part of, members, member of, pertains to and more.
- Favorite terms.
- Word browsing history.
- Add your own notes to any term.
- Audio pronunications.
- Wildcard (?,*) searching.
- Spelling suggestions.
- Fast, reliable, iCloud (CloudKit) sync and backup of history, favorites, notes and actions.
- Term of the day.
- Alternate App icons.
- Dark theme.

### Extensible Actions

Actions provide quick links to lookup and search your terms on websites and in other apps. Ready to use actions for popular reference sites like Wikipedia,, Google, IMDb, Snopes and more, or create your own with simple URL templates.

### All the Latest Technologies

- Drag and drop text into Terminology to lookup, or drag out full text definitions and related words to other apps!
- Select alternate home screen icon!
- Share extension lets you access Terminology from a text selection in any app.
- Today widget for quick access.
- Drag and drop.
- 3D Touch support.
- iPad Multitasking/Split View support.
- Spotlight and Handoff support.

### More Features

- Extensive support for URL scheme integration via x-callback-url. Visit our website for details.
- Great support for Accessibility features like VoiceOver and Dynamic Text.

### About the Dictionary

- Terminology's offline dictionary is based on the latest 3.1 version of the Princeton University WordNet project and contains U.S. English words.


We love to hear your feedback, please contact us.

Twitter/ @terminologyapp

What’s New

Version 4.4.4

Fix for crash adding actions on iPad.

Ratings and Reviews

4.7 out of 5
675 Ratings

675 Ratings

Jayde J. ,

Reliable developer.

I bought this app about 2 years ago. However, I haven't used it because of lacking free storage (sadly, my phone has small memory. ), so I haven't noticed it has been changed to freemium. I was pretty shocked and sent an inquiry mail to developer.
This developer always answers pretty fast... and also the developer gave me full explanation. I was touched little bit ;)

When I buy an app, the sustainability of app is really important because some developers usually give up their app after few years. I think this developer has big responsibility on this app.
Thanks, developer and thanks for the great app. I recommend you to use it☺️

Teenals ,

Not Accurate {read: dishonest?}

The definitions are not sourced from a sober reliable source like Merriam-Webster or Oxford. They come from Princeton University’s WordNet Lexical database. The words in this database are written by WordNet’s lexicographers—BIASED lexicographers perhaps. If you read definitions for words like “progressive” or “conservative” and then compare those definitions and synonyms to said sober sources, you will notice quite a difference. Dictionaries are supposed to be objective reference books and not a setting for individuals to weight the focus of a definition toward ones personal world view. That’s dishonest. Now Agile Tortoise might be basically honest programmers who, focused on the machinery of making an elegant app, did not consider the purity of their source. But as any programmer knows, garbage in, garbage out. This tool is passing through some garbage from WorldNet, which has some of ITS source from a common lexicon from New York University called COMLEX. So it is unclear where the pollution entered the system. It could have been a dishonest NYU student who put a personal touch in while working on the project, who knows. But you can see how disinformation slips in in large complicated systems where people are too busy to proctor the details. Just be forewarned to take some of these definitions with a grain of salt. This is no “American Heritage” dictionary.

Pixietale ,

Bestest ever

I like the Oxford on macOS dictionary and all. Terminology, however, is absolutely my favorite reference because of the way it doesn’t only give you the definition you’re looking for, it actually helps you to know it’s the right word you need and if not, where to find it.

I *had* to add Terminology dictionary to my Mac also (visit their web site to get it and see how).

Love this app. Even though removing adverts from the free version isn’t something I felt any urge to do, I upgraded to the “Pro” version for no reason other than to support this developer as they are on the ball. Upgrade to iOS 11? Yep, there’s a Terminology for that.


Agile Tortoise
75.7 MB

Requires iOS 13.0 or later. Compatible with iPhone, iPad, and iPod touch.



Age Rating
In-App Purchases
  1. Pro $1.99


  • Family Sharing

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

More By This Developer

You May Also Like