outerType

Outer type of this type, if this type's classifier is an inner class. For example:

class A { inner class B }

fun foo(a: A<*>.B) {}

The type of the foo's parameter in the metadata is B<Byte> (a type whose classifier is class B, and it has one type argument, type Byte?), and its outer type is A<*> (a type whose classifier is class A, and it has one type argument, star projection).