Inexkin

Inex-kin
Inexkin is a term for a kintype that cannot be described, named, or understood. This does not mean that the kintype is unknown; rather, the kintype itself is some sort of thing that can’t be understood or described due to its nature. It is possible that the user understands their kintype innately, but it is unable to be described or comprehended by other people.

This was primarily made in mind of those who have a nonhuman kintype(s) that are so detached from humanity, that describing them feels impossible. This may include some kinds of eldritch beings, as well as other kinds of entities such as shadow/void people, and so on. Comes from the word “inexplainable.”

This term was coined by extranth on Tumblr.

Terminology
This term falls under inexian/inexbeing, which is where someone's alterhuman identity cannot be described, named, or understood. This is also an Otherkin identity.