---
title: domain
framework: healthkit
role: symbol
role_heading: Instance Property
path: healthkit/hkhealthconceptidentifier/domain
---

# domain

The domain this identifier belongs to.

## Declaration

```swift
var domain: HKHealthConceptDomain { get }
```

## Discussion

Discussion This value identifies the group of concepts the identifier comes from. For example, if the identifier represents a medication, the category will be the medication domain.