## Definition of diagonal

**:**joining two vertices of a rectilinear figure that are nonadjacent or two vertices of a polyhedral figure that are not in the same face

**:**passing through two nonadjacent edges of a polyhedron

- a diagonal plane

**:**inclined obliquely from a reference line (such as the vertical)

- wood with a diagonal grain

**:**having diagonal markings or parts

- a diagonal weave