Perpendicular Blade

knife edge ground close to perpendicular to the long axis of the handle

Contrast parallel blade, oblique blade.

photo of a lineup of knives showing progressively more parallel angles of edges to handle axes
This lineup of knives shows a progression of edge-to-handle angles from perpendicular to parallel. Shown: Craft Sha 8667, Craft Sha 8669, TINA 270G, Hyde Mill Blade in Dexter handle.