It cannot be named. But if we wish to speak of it we offer a name in the knowledge of the names inadequacy.
The Absolute, Awareness, The Self, Consciousness, Brahman, The Universe, God.
Some shrink from calling it God because of the connotations of a separate Being in the sky. They say God is a human-made concept.
I don’t mind using the term God at all, because for me it represents the attribute-less All, while evoking reverence and awe.
It doesn’t matter what we call it. Any word, or description, falls infinitely short. Choose then the term or terms which best invoke the truth for you.