<!--
{
  "availability" : [
    "iOS: 17.0.0 -",
    "iPadOS: 17.0.0 -",
    "macCatalyst: 17.0.0 -",
    "macOS: 14.0.0 -",
    "tvOS: 17.0.0 -",
    "visionOS: 1.1.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "Speech",
  "identifier" : "/documentation/Speech/SFCustomLanguageModelData/CustomPronunciation",
  "metadataVersion" : "0.1.0",
  "role" : "Structure",
  "symbol" : {
    "kind" : "Structure",
    "modules" : [
      "Speech"
    ],
    "preciseIdentifier" : "s:6Speech25SFCustomLanguageModelDataC19CustomPronunciationV"
  },
  "title" : "SFCustomLanguageModelData.CustomPronunciation"
}
-->

# SFCustomLanguageModelData.CustomPronunciation

A term to be introduced into the speech recognition model’s vocabulary.

```
struct CustomPronunciation
```

## Overview

Attempts to add terms that are already in the model’s vocabulary will be ignored.
Pronunciations that use X-SAMPA symbols that are not supported will be ignored;
see [`supportedPhonemes(locale:)`](/documentation/Speech/SFCustomLanguageModelData/supportedPhonemes(locale:)) for the set of supported symbols.

## Topics

### Creating a term

[`init(grapheme: String, phonemes: [String])`](/documentation/Speech/SFCustomLanguageModelData/CustomPronunciation/init(grapheme:phonemes:))

### Inspecting a term

[`let grapheme: String`](/documentation/Speech/SFCustomLanguageModelData/CustomPronunciation/grapheme)

The written representation of the term, the way it is expected to appear in transcriptions.

[`let phonemes: [String]`](/documentation/Speech/SFCustomLanguageModelData/CustomPronunciation/phonemes)

Zero or more phonetic representations of the term, given as X-SAMPA strings.

## Relationships

### Conforms To

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`DataInsertable`](/documentation/Speech/DataInsertable)

[`Sendable`](/documentation/Swift/Sendable)

[`Equatable`](/documentation/Swift/Equatable)

[`Decodable`](/documentation/Swift/Decodable)

[`Hashable`](/documentation/Swift/Hashable)

[`Encodable`](/documentation/Swift/Encodable)

---

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)