Lexicontext: Offline English Dictionary Library for iOS Apps


Lexicontext is a free offline English dictionary component for iOS apps. It was built for developers who want to add an in-app dictionary to their iPhone, iPad or iPod apps using the iOS SDK.

As an illustration of the potential value of Lexicontext, consider the value provided by the offline dictionaries of Kindle for iOS and Apple's iBooks. Lexicontext can also be used for building word games, educational apps, etc.

Lexicontext is provided as a static library with a simple Objective-C API that allows you to lookup the definition of a word and get the result in either plain-text or HTML.

Lexicontext is already embedded in dozens of apps.

Main Features

  • More than 150,000 words
    Lexicontext contains the complete WordNet dictionary which includes more that 150,000 English word definitions.
  • Thesaurus
    Get lists of words, grouped together according to similarity of their meaning (synonyms).
  • Works with Swift
    Lexicontext can be easily used in Swift apps.
  • Fast
    Looking up a word definition is instantaneous and takes a small fraction of a second.
  • Network not required
    The dictionary is bundled with your app, so your users don't need a network connection and can use your app anywhere.
  • Customizable & flexible
    Definitions can be fetched as plain-text, HTML or as a structured NSDictionary. You can use CSS to format HTML definitions.
  • Small memory footprint
    Lexicontext consumes about 300K at runtime. The dictionary data can be bundled with your app or downloaded separately after the installation.
  • Powerful search
    Words can be looked up by their prefix or by a search pattern.
  • Drill into new words
    With HTML definitions, users can touch a word and drill into its definition.
  • Audio pronunciation
    The free Lexicontext Pronounce add-on provides audio pronunciation of a given dictionary word.
  • Trivial to bundle
    To add Lexicontext to your app, link to a single library, import a single header file, add a single data Bundle to your app's resources and you're done.
  • Easy to use
    Lexicontext's API is lean. How you want to present the word definitions to your user is up to you and Lexicontext doesn't force you into any specific user interface.
  • Expandable
    You can add your own new definitions to the dictionary at runtime or at build-time.
  • Word images
    Via the the ImageNet service Lexicontext provides access to the images of a given dictionary word.
  • Lexicontext is compatible with iOS 8 and higher

Source Code

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