Definitions

1. noun

a line or shape that cuts through a figure from one corner to the opposite corner, forming an angle of 90°; a line or shape that is not horizontal or vertical.

“The architect designed a room with a diagonal beam to support the roof.”

2. adjective

relating to or forming a diagonal line or shape.

“The diagonal pattern on the fabric added a unique touch to the dress.”

3. verb

to form a diagonal line or shape.

“The artist diagonalled the canvas with bold brushstrokes.”