What is same as Unguis, 3. Spherical ungula (Geom.), a part of a sphere bounded by two planes intersecting in a diameter and by a line of the surface of the sphere called?

ungula — (Bot.) Same as Unguis, 3. Spherical ungula (Geom.), a part of a sphere bounded by two planes intersecting in a diameter and by a line of the surface of the sphere. (Webster's 1913.)

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