orthogonal

adjective

1. 1

   having a set of mutually perpendicular axes; meeting at right angles

   wind and sea may displace the ship's center of gravity along three orthogonal axes

   a rectangular Cartesian coordinate system

2. 2

   statistically unrelated

3. 3

   not pertinent to the matter under consideration

   an issue extraneous to the debate

   the price was immaterial