Huh?

The term 3-dimensional means as in an X-Y-Z space. (height, width depth).

How can you have a 2d, 3rd, or 4th dimension? 2-dimensional simply means only in an X-Y space (objects only have a surface, no interior.. width, height, no depth)

Most people assume that we live in 3-dimensional space, but this is wrong. We actually live in 4-dimensional space; the 4th dimension is time.

i have no idea what the 5th, 6th, or 7th dimensions would be, though.. let alone the 11th