# Parameter Vocabularies The keys you include in your global vocabulary file to describe app-specific terms. ## Discussion The `ParameterVocabularies` key contains the custom terminology that is global to all users of your app. This key contains an array of dictionaries, each of which defines a set of terms and the intent properties to which those terms apply. The keys for the dictionary are as follows: - `ParameterNames`: (Required) An array of strings, each of which contains a key path for a property name from an intent class. For example, to specify a custom ride option for a ride request intent, specify the key path `INRequestRideIntent.rideOptionName`. - `ParameterVocabulary`: (Required) An array of dictionaries containing the custom terms to associate with the specified properties. Each dictionary contains the following keys. - `VocabularyItemIdentifier`: (Required) The string that Siri assigns to the identifier property of the `INSpeakableString` object when it recognizes your custom vocabulary. This identifier applies to all synonyms. - `VocabularyItemSynonyms`: (Required) An array of dictionaries that define the phrases for Siri to recognize. Use the following keys in the dictionary to specify the phrase, pronunciation hints, and examples: - `VocabularyItemPhrase`: (Required) A string containing the custom phrase that you want to define. Spell the phrase the same way that your app uses it. - `VocabularyItemPronunciation`: (Optional) A string containing pronunciation hints for the phrase, formatted in a “sounds like” format. For example, the pronunciation for the phrase “iTunes” might be “eye toons”. - `VocabularyItemExamples`: (Optional) An array of strings, each of which contains examples of how to use the phrase. Xcode helps you add terms to your vocabulary file. When you create a property list file with the name `AppIntentVocabulary.plist`, Xcode knows that the file should contain custom vocabulary, and it makes only the relevant keys available in the property list editor. The figure below shows an example of a global vocabulary file in Xcode that contains custom terms for a workout app.  ## See Also --- Copyright © 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)