iOS 13.2 adds the ability to delete your Siri and Dictation history on any iOS device. Here's how to clear your Siri search/request and Dictation history:
- Open the Settings app on your device.
- Tap Siri.
- Tap Siri & Dictation History.
- Tap Delete Siri & Dictation History.
From here you can also read about "Improve Siri & Dictation." Apple will store samples of your audio interactions with Siri and Dictation if you do not disable this feature. Improve Siri & Dictation allows Apple employees to "review a sample of audio interactions with Siri and Dictation in order to help Apple develop and improve Siri, Dication, and other language processing features like Voice Control."
You can read all about Improve Siri & Dictation by tapping the blue "About Improve Siri & Dictation link in the Siri & Search settings on your iOS device. Click here to learn how to disable/opt out of Improve Siri & Dictation.