- The definition of diagonal is something with slanted lines or a line that connects one corner with the corner furthest away.
An example of diagonal is a line going from the bottom left corner of a square to the top right corner.
A piece of fabric with diagonal stripes.
- extending between the vertices of any two nonadjacent angles in a polygonal figure or between any two vertices not in the same face in a polyhedral figure; extending slantingly between opposite corners
- moving or extending obliquely, esp. at a 45° angle; slanting
- having slanting markings, lines, etc.
Origin of diagonalClassical Latin diagonalis ; from Classical Greek diagōnios ; from dia-, through + gōnia, an angle, corner: see knee
- a diagonal line or plane
- any diagonal course, row, order, or part
- cloth woven with diagonal lines; twill
- Mathematics a. Joining two nonadjacent vertices of a polygon.b. Joining two vertices of a polyhedron not in the same face.
- Having a slanted or oblique direction.
- Having oblique lines or markings.
- Relating to or being the front left and back right feet or the front right and back left feet of a quadruped.
- Mathematics A diagonal line or plane.
- Something, such as a row, course, or part, that is arranged obliquely.
- A fabric woven with diagonal lines.
- A virgule.
Origin of diagonalLatin diagōnālis, from Greek diagōnios, from angle to angle : dia-, dia- + gōniā, angle, corner; see genu-1 in Indo-European roots.
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