What is the noun of identity?

The noun of "identity" is simply identity itself. It's a noun that already exists in its noun form.

However, depending on the context, there are other related nouns you could use:

* Identification: This refers to the act of identifying something or someone.

* Self: This refers to a person's individual being, which is a key component of identity.

* Persona: This refers to the outward appearance or character that a person presents to the world, which can be a part of their identity.

* Character: This refers to the distinctive qualities that define a person or group, which are also part of their identity.

It's important to choose the noun that best suits the meaning you want to convey.