From HomoExcelsior

1. Joining two nonadjacent vertices of a polygon. 2. Joining two vertices of a polyhedron not in the same face. 3. Having a slanted or oblique direction. 4. Having oblique lines or markings. 5. A diagonal line or plane. 6. Something, such as a row, course, or part, that is arranged obliquely. 7. A fabric woven with diagonal lines.

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