Antonyms of adj crabwise

1 sense of crabwise

Sense 1
crabwise, sideways -- ((of movement) at an angle)

INDIRECT (VIA perpendicular, oblique) -> parallel -- (being everywhere equidistant and not intersecting; "parallel lines never converge"; "concentric circles are parallel"; "dancers in two parallel rows")
INDIRECT (VIA oblique, parallel) -> perpendicular -- (intersecting at or forming right angles; "the axes are perpendicular to each other")

Similarity of adj crabwise

1 sense of crabwise

Sense 1
crabwise, sideways -- ((of movement) at an angle)
       => oblique (vs. parallel) (vs. perpendicular) -- (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")