Anirvacanīya, “that which cannot be defined”, is how Advaita characterizes the world of appearance. It cannot be called real, for it is sublated by knowledge, nor unreal, for it is experienced, nor both, which is contradictory. Critics in other schools argued that this was a confession of incoherence.
Anirvacanīya
Indescribable: the Advaita term for the status of māyā and the world, neither real nor unreal.
Also: Anirvachaniya