magnitude (magnitud)

[= F. magnitude = Sp. magnitud = Pg. magnitude = It. magni tudine, With plain heroick magnitude of mind. Milton, S. A., 1. 1279. We commonly find in the ambitious man a superiority of parts, in some measure proportioned to the magnitude of his designs. Horsley, Works, I. iv. 3577 2. Largene of relation or significance; importance; consequence: as, in affairs of mag nitude disdain not to take counsel.-3. Size, or the property of having size; the extended quantity of a line, surface, or solid; length, area, or volume. And fast by, hanging in a golden chain, This pendent world, in bigne as a star Of smallest magnitude. Magosphæra changes in the absolute magnitude of the object, and so reach a more precise and scientific statement of this particular aspect of the coexistence between body and mind. J. Sully, Sensation and Intuition, p. 44. 4. Any kind of continuous quantity which is comparable with extended quantity. In this sense we speak of the magnitude of a velocity, force, acceleration, or other vector quantity; but we do not properly speak of a magnitude of heat, energy, temperature, sound, etc. The use of the word as a synonym of quantity, as in the following pa age, is to be deprecated. By intensive magnitude is meant the strength of a sen (A. P. de Candolle, 1818), speaking corresponds to the area of the sentient surface and the number of nervous elements acted upon. J. Sully , Sensation and Intuition, p. 44. 5. In astron., the brightne of a star expre ed according to the numerical system used by astronomers for that purpose. In this sense magnitude translates Greek μέγεθος, used in the same sense in the Almagest, the expre ion being due to the fact that bright stars, by an effect of irradiation, look larger than faint ones. The brightest stars are said to be of the first magnitude, while those of the sixth magnitude are hardly noticed by casual observers in ordinary states of the sky. Since the brightne of stars has been measured photometrically, the terval between succe ive magnitudes has been defined by a constant ratio of brightne , which in the so-called ab solute scale, now generally used, is 100, or 2.51. 6. In anc. pros., the length of a syllable, foot, colon, or meter, expre ed in terms of the metrical unit (primary time, semeion, or mora): as, a foot of trisemic magnitude; a colon of icosasemic magnitude. Absolute magnitude. See abso lute. - Angular magnitude, the quantity of an angle. Apparent magnitude of an object, that magnitude which is measured by the optic or visual angle intercept ed between lines drawn from the extreme points of the object to the center of the pupil of the eye. This angle may be considered to be inversely as the distance of the object. [This phrase is used chiefly with reference to the heavenly bodies, but is employed also in many branches of optical science, with the same general meaning.]-Center of magnitude. See center1.=Syn. Bulk, Volume, etc. See size .