a. Joining two nonadjacent vertices of a polygon.
b. Joining two vertices of a polyhedron not in the same face.
2. Having a slanted or oblique direction.
3. Having oblique lines or markings.
4. Relating to or being the front left and back right feet or the front right and back left feet of a quadruped.
1. Mathematics A diagonal line or plane.
2. Something, such as a row, course, or part, that is arranged obliquely.
3. A fabric woven with diagonal lines.
4. A virgule.
[Latindiagōnālis, fromGreekdiagōnios, from angle to angle : dia-, dia- + gōniā, angle, corner; see genu-1 in the Appendix of Indo-European roots.]
(click for a larger image)diagonal
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