Possessing all three
spatial dimensions:
height,
width, and
depth. A
sphere, a
cube, and a
pyramid are all simple
geometric three-dimensional figures. When contrasted with a
four-dimensional object, a three-dimensional object does not change with
time.
In a literary context, a three-dimensional character is one possessing ambitions, motives for those ambitions, and a clear history to explain those motives. Three-dimensional are the most believeable kind and take the most time to write, which is why your average writer will settle for the two-dimensional sort.