See also: Extraplanar

The term extradimensional describes a metaphysical existence outside of any plane or dimension. (The term nondimensional is synonymous.) For example, a bag of holding stores objects in a tiny extradimensional space that does not exist on any dimension, including the dimension on which the container itself exists.[1]

Extradimensional spaces can serve many functions, and are most often created as a result of magic, particularly spells and magic items.[1] For a list of magic related to extradimensionality, see Category:Extradimensional magic.

Reactions between extradimensional objects

Extradimensional spaces can be subject to unusual reactions when combined. For instance, placing an extradimensional container into the extradimensional space of a rope trick. Doing so prevents access to the container's extradimensional space until the container is removed from the space. Another example involves direct interactions between a bag of holding and a portable hole, which can destroy or exile both objects and create a planar rift or portal to the Astral Plane.[1][2]