<!--
{
  "availability" : [
    "iOS: 8.0.0 -",
    "iPadOS: 8.0.0 -",
    "macCatalyst: 13.1.0 -",
    "tvOS: -",
    "visionOS: 1.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "UIKit",
  "identifier" : "/documentation/UIKit/UIInputViewController/requestSupplementaryLexicon(completion:)",
  "metadataVersion" : "0.1.0",
  "role" : "Instance Method",
  "symbol" : {
    "kind" : "Instance Method",
    "modules" : [
      "UIKit"
    ],
    "preciseIdentifier" : "c:objc(cs)UIInputViewController(im)requestSupplementaryLexiconWithCompletion:"
  },
  "title" : "requestSupplementaryLexicon(completion:)"
}
-->

# requestSupplementaryLexicon(completion:)

Obtains a supplementary lexicon of term pairs in a custom keyboard.

```
func requestSupplementaryLexicon(completion completionHandler: @escaping (UILexicon) -> Void)
```

## Parameters

`completionHandler`

Code that you write to make use of the returned `UILexicon` object.

## Discussion

Call this method to obtain a [`UILexicon`](/documentation/UIKit/UILexicon) object containing a basic set of term pairs for use in autocorrection or textual suggestions based on user input. The [`UILexicon`](/documentation/UIKit/UILexicon) object contains words from various sources, including:

- Unpaired first names and last names from the user’s Address Book database
- Text shortcuts defined in the Settings > General > Keyboard > Shortcuts list
- A common words dictionary

Consider this lexicon as a supplement to a more complete lexicon of your own design.

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)