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# NSView.DefinitionOptionKey

Keys to include in your definition.

```
struct DefinitionOptionKey
```

## Topics

### Option Key

[`static let presentationType: NSView.DefinitionOptionKey`](/documentation/AppKit/NSView/DefinitionOptionKey/presentationType)

An optional key in the options dictionary that specifies the presentation type of the definition display.

### Initializers

[`init(rawValue: String)`](/documentation/AppKit/NSView/DefinitionOptionKey/init(rawValue:))

## Relationships

### Conforms To

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

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

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

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

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

---

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