5th Dimension

So I’m not a mathematician or anything but I woke up this morning randomly thinking about dimensions and how we describe them. Anyways, here is my question.

What comes after "In, Out"? Looking for 5th dimension vocabulary. Heres how I’ve been stacking them in my head:

1D: Up, Down

2D: Up, Down, Left, Right

3D: Up, Down, Left, Right, Forward, Backward

4D: Up, Down, Left, Right, Forward, Backward, In, Out

5D: ???