diagonal - an oblique line of squares of the same color on a checkerboard

Example:- the bishop moves on the diagonals

diagonal, separatrix, slash, solidus, stroke, virgule - a punctuation mark (/) used to separate related items of information

bias, diagonal - a line or cut across a fabric that is not at right angles to a side of the fabric

diagonal - (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

diagonal - (geometry) a straight line connecting any two vertices of a polygon that are not adjacent

aslant, aslope, diagonal, slanted, slanting, sloped, sloping - having an oblique or slanted direction

diagonal - connecting two nonadjacent corners of a plane figure or any two corners of a solid that are not in the same face

Example:- a diagonal line across the page

Source : WordNet