The Absolute is what remains when every condition is set aside. It is Brahman in Hindu thought, the Godhead behind God in Meister Eckhart, the Dao that cannot be named in Taoism, Ein Sof in Kabbalah.
It resists description because description draws boundaries, and the Absolute is what has no boundary. Traditions differ on whether it is personal or impersonal, and on the relation between the Absolute and the manifest — but nearly all insist that direct encounter is possible, and that this is what the path is ultimately for.