Antonyms of adj antiparallel

1 sense of antiparallel

Sense 1
antiparallel -- ((especially of vectors) parallel but oppositely directed; "antiparallel vectors")

INDIRECT (VIA oblique, parallel) -> perpendicular -- (intersecting at or forming right angles; "the axes are perpendicular to each other")
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")

Similarity of adj antiparallel

1 sense of antiparallel

Sense 1
antiparallel -- ((especially of vectors) parallel but oppositely directed; "antiparallel vectors")
       => parallel (vs. perpendicular) (vs. oblique) -- (being everywhere equidistant and not intersecting; "parallel lines never converge"; "concentric circles are parallel"; "dancers in two parallel rows")