Space extended upward; height; the elevation of an object above its foundation; as, the altitude of a mountain, or column; or the elevation of an object or place above the surface on which we stand, or above the earth; as, the altitude of a cloud or a meteor; or the elevation of one object above another; as, of a bird above the top of aa tree.

The elevation of a point, a star, or other object above the horizon. This is true or apparent altitude; true, when taken from the rational or real horizon; apparent, when taken from the sensible, or apparent horizon.

Figuratively, high degree; superior excellence; highest point of excellence. He is proud to the altitude of his virtue. The altitude of the eye, in perspective, is a right line let fall from the eye, perpendicular to the geometrical plane. Meridian altitude is an arch of the meridian between the horizon and any star or point on the meridian.