# diagonal

A diagonal is made out of a straight line that's set at an angle instead of straight up or across. If you picture a square and draw a line connecting the opposite corners, that’s a diagonal line.

You’ll find diagonal lines in geometry, and also in the world around you. A quarterback might throw a diagonal pass that angles across the field, or you might buy a snazzy new leotard with diagonal stripes. Diagonal can be either a noun or an adjective. You could call the steep slope of a hill a diagonal across the sky, or you could talk about the diagonal hillside reaching up toward the clouds.

Definitions of diagonal
1

### adj having an oblique or slanted direction

Synonyms:
aslant, aslope, slanted, slanting, sloped, sloping
inclined
at an angle to the horizontal or vertical position

### adj 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”
Synonyms:
oblique
slanting or inclined in direction or course or position--neither parallel nor perpendicular nor right-angled

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

Type of:
straight line
a line traced by a point traveling in a constant direction; a line of zero curvature

### n a line or cut across a fabric that is not at right angles to a side of the fabric

Synonyms:
bias
Type of:
straight line
a line traced by a point traveling in a constant direction; a line of zero curvature

### n (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

Type of:
set
(mathematics) an abstract collection of numbers or symbols

### n an oblique line of squares of the same color on a checkerboard

“the bishop moves on the diagonals
Types:
main diagonal, principal diagonal
the diagonal of a square matrix running from the upper left entry to the lower right entry
secondary diagonal
the diagonal of a square matrix running from the lower left entry to the upper right entry
Type of:
line
a formation of people or things one behind another
line
a formation of people or things one beside another

### n a punctuation mark (/) used to separate related items of information

Synonyms:
separatrix, slash, solidus, stroke, virgule
Type of:
punctuation, punctuation mark
the marks used to clarify meaning by indicating separation of words into sentences and clauses and phrases