(mathematics) a set of entries in a square matrix running diagonally either from the upper left to lower right entry or running from the upper right to lower left entry
an oblique line of squares of the same color on a checkerboard; "the bishop moves on the diagonals"
a line or cut across a fabric that is not at right angles to a side of the fabric
(geometry) a straight line connecting any two vertices of a polygon that are not adjacent
at an angle; especially connecting two nonadjacent corners of a plane figure or any two corners of a solid that are not in the same face; "a diagonal line across the page"
being or affecting or concerned with a surface; not deep or penetrating emotionally or intellectually; "superficial similarities"; "a superficial mind"; "his thinking was superficial and fuzzy"; "superficial knowledge"; "the superficial report didn't give the true picture"; "only superficial differences"
of little substance or significance; "a few superficial editorial changes"; "only trivial objections"
relating to a surface; "superficial measurements"; "the superficial area of the wall"
one of several parallel layers of material arranged one on top of another (such as a layer of tissue or cells in an organism or a layer of sedimentary rock)