- 1perpendicular (to something) (technology) forming an angle of 90° with another line or surface; vertical and going straight up Are the lines perpendicular to each other? The staircase was almost perpendicular (= very steep).
- 2Perpendicular (architecture) connected with a style of architecture common in England in the 14th and 15th centuries, that makes use of vertical lines and wide arches
Check pronunciation: perpendicular