What does "diagonal" mean?

Diagonal: A right line drawn from one angle to another not adjacent, of a figure of four or more sides, and dividing it into two parts.

Additional senses

  1. 2.(Engin.) A member, in a framed structure, running obliquely across a panel.
  2. 3.A diagonal cloth; a kind of cloth having diagonal stripes, ridges, or welts made in the weaving.

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