| 释义 |
magnitude|ˈmægnɪtjuːd|
[ad. L. magnitūdo, f. magn-us great, cogn. w. Gr. µέγας, OTeut. *mikilo-: see much. Cf. OF. magnitude.]
1. The quality or fact of being great, in various senses; = greatness.
†a. Greatness of character, rank, or position. Also jocularly, as a title of address. Obs.
1398Trevisa Barth. De P.R. i. (1495) 3 Our wytte maye be led to the consyderacyon of the gretnesse, or magnytude, of the moost excellent bewteuous clarete dyuyne & Inuysyble. 1432–50tr. Higden (Rolls) III. 117 This Nabugodonosor transcendede in magnitude and fortitude Hercules in his actes. 1609B. Jonson Masque Queens Wks. 1616 I. 961 [Boadicea's] orations..wherein is expressed all magnitude of a spirit, breathing to the libertie and redemption of her Countrie. 1620Shelton Quix. III. xxxii. 231 And, for proof of this, let me tell your Magnitudes [etc.]. 1647Clarendon Hist. Reb. i. §141 The two Secretaries of State (which were not in those days officers of that magnitude they have been since..) were [etc.]. 1665Manley Grotius' Low C. Warres 741 The United States did not omit forthwith to send an Embassy to congratulate him [King James] for his new access of magnitude.
b. In physical sense: Greatness of size or extent. † Of sound: Loudness. Obs.
c1420Pallad. on Husb. i. 1066 To bey thy been biholde hem riche and fulle, Or preve hem by their murmurs magnitude. 1432–50tr. Higden (Rolls) I. 127 Profitable waters and wholsome, whiche be callede sees what for the magnitude of theyme and for the copious multitude of fisches. 1640Wilkins New Planet ii. (1684) 149 'Tis said, that Magnitude does always add to the swiftness of a violent motion. 1650Bulwer Anthropomet. xxi. 230 That which fails in magnitude is called smal. 1727De Foe Syst. Magic i. i. (1840) 9 The height, and strength, and magnitude of their building could only serve to make its fall..more terrible. 1817Chalmers Astron. Disc. i. (1852) 22 We have something more than the mere magnitude of the planets to allege in favour of the idea that they are inhabited. 1860Tyndall Glac. i. xi. 82 And as our eye ranged over the broad shoulders of the mountain,..the conception of its magnitude grew upon us.
c. Of immaterial things: Great amount or importance.
1432–50tr. Higden (Rolls) II. 343 He [Saturnus] was..namede as godde of alle goddes for the magnitude of his power. 1526Pilgr. Perf. (W. de W. 1531) 268 b, And how the effectes yt suche ioye of y⊇ spiryt leueth behynde it, sheweth y⊇ magnitude or greatnes therof. 1769Junius Lett. xxiii. 108 A great man,..even in the magnitude of his crimes, finds a rescue from contempt. a1806Horsley Serm. I. iv. (1816) 70 We commonly find in the ambitious man a superiority of parts, in some measure proportioned to the magnitude of his designs. 1844Thirlwall Greece lx. VIII. 29 The preparations..were..on a scale proportioned to the magnitude of the object he had in view. 1861Stanley East. Ch. vi. (1869) 189 No conversion of such magnitude [as that of Constantine] had occurred since the Apostolic age.
2. a. Size whether great or small; in geometrical use, the measure or extent of a particular line, area, volume, or angle.
1570Billingsley Euclid i. i. 1 A signe or poynt..is the beginning of magnitude. 1599A. M. tr. Gabelhouer's Bk. Physicke 74/1 Mixe of this poulder the magnitude of a hasell⁓nutte amongst a little Cotten. 1615Crooke Body of Man 355 It is a Membrane enclosing the whole cauity of the Chest, wherefore his Figure and magnitude is answerable to that cauity. 1658Rowland tr. Moufet's Theat. Ins. 1080 It is a small creature, and contemptible for its magnitude. 1725De Foe Voy. round World (1840) 284 As to the magnitude of those rivers, he could say little. 1754Sherlock Disc. (1759) I. iv. 159 Reason can measure the Magnitudes and Distances of the heavenly Bodies. 1840Lardner Geom. v. 59 We can never obtain an arc of the precise value of any one of the usual denominations of angular magnitude. 1854Brewster More Worlds v. 94 The creations of the material world, whether they be of colossal or atomic magnitude. 1885Watson & Burbury Math. Th. Electr. & Magn. I. 119 Two infinite series of images, the magnitudes or values of which converge.
b. quasi-concr.
1570Dee Math. Pref. 3 What Magnitude so euer, is Solide or Thicke, is also broade, and long... A long magnitude, we terme a Line. 1570Billingsley Euclid v. ix. 141 Magnitudes which haue to one and the same magnitude one and the same proportion: are equall the one to the other. 1859Barn. Smith Arith. & Algebra (ed. 6) 192 The term Magnitude or Quantity is used in Mathematics to express whatever is capable of increase or diminution. Thus a sum of money is a magnitude or quantity. 1864Bowen Logic iv. 66 A Concept is a magnitude or Quantity.
c. The intrinsic size of an earthquake or underground explosion (as distinguished from the intensity of its effects at any particular place), usu. expressed by a number that is a logarithmic function of the maximum resulting seismometric deflection adjusted to allow for distance.
The use shown in quot. 1830 under sense 3 c is unrelated.
1935C. F. Richter in Bull. Seismol. Soc. Amer. XXV. 1 In the course of historical or statistical study of earthquakes in any given region it is frequently desirable to have a scale for rating these shocks in terms of their original energy, independently of the effects which may be produced at any particular point of observation. On the suggestion of Mr. H. O. Wood, it is here proposed to refer to such a scale as a ‘magnitude scale’. Ibid. 2 The requirements of research..call for some estimate of the magnitude, in the sense here used, of each important shock in the California region. 1947K. E. Bullen Introd. Theory Seismol. xiv. 234 The smallest earthquakes reported felt are of magnitude 1·5;..those of magnitude 4·5 are capable of causing slight damage near the epicentre. 1959B. F. Howell Introd. Geophysics ix. 125 Values of magnitude calculated at different observatories, using different seismometers at one observatory, or even different phases (body or surface waves) on the same seismogram, may be different. 1971Daily Colonist (Victoria, B.C.) 7 Feb. 1/1 The quake had a magnitude of 6·7 on the Richter scale. 1972Sci. Amer. Jan. 14/3 Underground explosions in the megaton range can have a body-wave magnitude of 6·5 to 7.
3. A class in a system of classification determined by size.
a. Each of the classes into which the fixed stars have been arranged according to their degree of brilliancy. Now regarded as a number on a continuous scale representing the negative logarithm of the brightness, such that a decrease of five magnitudes represents a hundred-fold increase in brightness and a decrease of one magnitude an increase of 2·512 times.
The stars ‘of the first magnitude’ are the most brilliant; the ‘sixth magnitude’ includes those that are barely visible to the naked eye; the seventh and lower magnitudes are telescopic only. The classification into ‘magnitudes’, originally somewhat loose, as depending on the estimate formed by the individual observer, is now a matter of photometric measurement. The word magnitude in this application is a literal rendering of the Gr. µέγεθος, used by Ptolemy. Formerly often denoted by the symbol m, as 2.m, 3.m.
Before decimal or fractional numbers were used there was an intermediate stage illustrated by quots. 1796, 1826 (and also 1851).
[1594Blundevil Exerc. iv. xxxi. (1636) 485 The fift sheweth the magnitude or greatnesse of the starre, whether it be of the first, second, or third bignesse.] a1641Bp. R. Montagu Acts & Mon. (1642) 121 In the firmament of heaven be many Starres;..of the first, second, third magnitude, as they use to speak. 1667Milton P.L. vii. 357 He form'd the Moon Globose, and everie magnitude of Starrs. 1690Leybourn Curs. Math. 383 A star of the 1 Magnitude may be seen when the Sun is but 12 deg. below the Horizon. 1796W. Herschel in Phil. Trans. R. Soc. LXXXVI. 168, 1.2m for instance, denotes that a star so marked is between the first and second magnitude. 2.1 signifies the same thing, with an intimation that the star so marked is nearly at the second magnitude, but partakes still something of the lustre of a star of the first order. 1826J. F. W. Herschel in Mem. R. Astron. Soc. II. 444, I shall extend the examination to all stars of the 8th and (8·9) magnitudes; those of the 9th however not included. 1851Monthly Notices R. Astron. Soc. XI. 187 The differences..clearly show that widely different scales of magnitude have been adopted. Ibid., This triple star..is designated by Argelander..as of magnitude 5·4 (or about 4·7). 1893Sir R. Ball Story of Sun 13 A star of about the eighth magnitude. 1897D. P. Todd New Astron. xvi. 423 Even the surpassing brilliancy of the sun can be indicated on the same scale; the number - 25·4 expresses his stellar magnitude. 1902Daily Chron. 11 Aug. 6/7 Eros will be detected by the naked eye as a sixth magnitude star. 1930R. H. Baker Astron. i. 20 The magnitude of the brightest star, Sirius, is -1·6; Canopus is -0·9. 1967C. M. Huffer et al. Introd. Astron. xvii. 248/2 The photoelectric photometer, under the best conditions and by averaging several observations, can make measures down to 0·001 magnitude in accuracy.
†b. Numism. Obs.
1705Hearne Collect. 19 Dec. (O.H.S.) I. 133 The said Coyns are all Brass of the 3d magnitude.
c. Occas. in other applications. Phr. of the first magnitude (fig.): of the utmost greatness or importance.
1693G. Stepny Juvenal Sat. viii. 47 Whatever be your Birth, you're sure to be A Peer of the First Magnitude to me. 1830Lyell Princ. Geol. I. 413 In the following year there were one hundred and fifty-one [sc. earthquake shocks: they were registered in four classes], of which ninety-eight were of the first magnitude. Mod. To do this would be a blunder of the first magnitude. |