Diagonal

(di-dg'o-ndl.) [From Gr. dia, through, and go nia, an angle.) (Geom.) A right line drawn acro a quadrilateral figure from one angle to another; it is by some called the diameter of the figure. No triangle can po e a D.; but a quadrilateral figure has two; a pentagon,five; a hexagon, nine; and so on. [s. 282]