Dimension

A dimension is an independent quantity which is used to describe an object. In a given mathematical space, there is a minimum number of dimensions required to completely describe an object's location and/or size. For example, a three dimensional object such as a sphere can be described with many different coordinate systems, but each system requires three values (rectangular coordinates being x-y-z, cylindrical r-theta-z, and spherical rho-phi-theta).

In some contexts, the term "dimension" is used to describe a realm of existence within which our universe is located.