Open English Wordnet
Adjectives
(s)extraneous, immaterial, impertinent, orthogonalnot pertinent to the matter under consideration“an issue extraneous to the debate”, “the price was immaterial”, “mentioned several impertinent facts before finally coming to the point”
(s)orthogonal, rectangularhaving 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”