A spatial thing type by dimensionality and a specialization of spatial thing with one or more dimensions. Each instance of thing with two or more dimensions is a spatial thing that has a dimensionality of two or higher, and thus is either a two- or three- (or higher-) dimensional spatial object.

Examples of PolyDimensionalThings include tangible or intangible spatially-localized polydimensional objects, such as the flat surface of a tabletop and the table itself, as well as abstract geometrical objects that are at least two-dimensional, such as a Platonic cube. Specializations of this collection include tangible thing, bilateral object, and two dimensional shape.