a figure having nine sides and angles. In a regular nonagon, or that whose angles and sides are all equal, if each side be 1, its area will be $6.181824^2 = \frac{3}{2}$ of the tangent of $75^\circ$, to the radius 1.

NON, Cape, a promontory on the west coast of Africa, opposite to the Canary islands. W. Long. 12°. N. Lat. 44°. 28'.