Antonyms of adj orthogonal

3 senses of orthogonal

Sense 1
extraneous, immaterial, impertinent, orthogonal -- (not 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")

INDIRECT (VIA irrelevant) -> relevant -- (having a bearing on or connection with the subject at issue; "the scientist corresponds with colleagues in order to learn about matters relevant to her own research")

Sense 2
orthogonal -- (statistically unrelated)

INDIRECT (VIA unrelated) -> related, related to -- (being connected either logically or causally or by shared characteristics ; "painting and the related arts"; "school-related activities"; "related to micelle formation is the...ability of detergent actives to congregate at oil-water interfaces")

Sense 3
orthogonal, rectangular -- (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")

INDIRECT (VIA parallel, perpendicular) -> oblique -- (slanting or inclined in direction or course or position--neither parallel nor perpendicular nor right-angled; "the oblique rays of the winter sun"; "acute and obtuse angles are oblique angles"; "the axis of an oblique cone is not perpendicular to its base")
INDIRECT (VIA perpendicular, oblique) -> parallel -- (being everywhere equidistant and not intersecting; "parallel lines never converge"; "concentric circles are parallel"; "dancers in two parallel rows")

Similarity of adj orthogonal

3 senses of orthogonal

Sense 1
extraneous, immaterial, impertinent, orthogonal -- (not 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")
       => irrelevant (vs. relevant) -- (having no bearing on or connection with the subject at issue; "an irrelevant comment"; "irrelevant allegations")

Sense 2
orthogonal -- (statistically unrelated)
       => unrelated (vs. related) -- (lacking a logical or causal relation)

Sense 3
orthogonal, rectangular -- (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")
       => perpendicular (vs. oblique) (vs. parallel) -- (intersecting at or forming right angles; "the axes are perpendicular to each other")