| 释义 |
elongation|iːlɒŋˈgeɪʃən|
Also 4 elongacioun.
[ad. late L. ēlongātiōn-em, n. of action f. ēlongāre: see elongate.]
1. Astr.
a. The angular distance of a heavenly body from some relatively fixed point; in mod. usage, the angular distance of a planet from the sun, or of a satellite from its primary.
c1391Chaucer Astrol. ii. §25 Take the heiest altitude..of any sterre fix..& tak his nethere elongacioun. 1540Dyfference of Astron. A ii b, Of sygnes, and of theyr elongations. 1647Lilly Chr. Astrol. 31 ☿ is in his greatest elongation or distance from the ☉. 1662Fuller Worthies ii. 237 The star Venus was visible all day long, as sometime it falls out neer her greatest Elongation. 1841Brewster Mart. Sc. iii. (1856) 35 We saw her [Venus] in the form of a crescent, resembling exactly the moon at the same elongation. 1868Lockyer Heavens (ed. 3) 76 In the morning..its maximum western elongation attains the same value.
†b. The difference in motion between the swifter and the slower of two planets, or the quantity of space whereby the one has overgone the other.
1727–51in Chambers.
†c. The difference between the true place and the geocentric place of a planet. Obs.
1796in Hutton.
†2.
a. Removal to a distance, departure, recession; hence, remoteness; also fig. Obs.
1616Bullokar, Elongation, a putting far off. 1639J. Symonds in Spurgeon Treas. Dav. Ps. xxxviii. 9 Ofttimes there is a frustration of our desires, or an elongation of the things. 1654tr. Scudery's Curia Politiæ, Those who designed his elongation and further removal from Court. 1661Hickeringill Jamaica 5 That vulgar errour, that it's [the Sun's] elongation [is] the reason of extreamity of cold. 1672Phil. Trans. VII. 5126 The Dis-appearance of those Stars may be ascribed to their Elongation from..our Eyes. 1694R. Burthogge Essay on Reason 140 In its utmost Elongation or Removal from him.
†b. Astron. The removal of a planet to its furthest distance from the sun; aphelion.
1715in Kersey. 1721–1800in Bailey. 1787Smeaton in Phil. Trans. LXXVII. 319 The same disappointment..with respect to the approaching elongation in September.
3. The action or process of elongating, lengthening out, or extending.
1731Arbuthnot Aliments 42 This Motion of Elongation of the Fibres. 1793T. Beddoes Math. Evid. 142 What overturns this whole system of analogical elongation..is a discovery..to which Lennep contributed an hint. 1828H. Steuart Planter's G. 277 This decided tendency to elongation of the boughs on the lee-side. 1831Brewster Nat. Magic iv. (1833) 80 The figure will undergo most curious elongations and contractions. 1878L. P. Meredith Teeth 47 There is also an elongation of the anterior portion of the jaws.
†4. Surgery.
a. ‘An imperfect luxation, when the ligaments are only relaxed and lengthened, but the bone is not out of place’ (Syd. Soc. Lex.).
1676Wiseman Surg. 480 Those Elongations which are the effect of an Humour soaking upon a Ligament..making it liable to be stretcht. 1715in Kersey. 1847in Craig.
b. ‘The extension of a limb for the purpose of reducing a dislocation or setting fractured bones’ (Syd. Soc. Lex.).
1847in Craig.
5. The state of being elongated or lengthened. concr. That which is elongated; an extended space, a continuation, a part produced.
1751R. Cambridge Scribbleriad iii. 83 note, His skin was..grown over with an horny excrescence called by the Naturalists the Elongation of the papillæ. 1796H. Hunter tr. St. Pierre's Stud. Nat. (1799) III. 29 To prove the truth of my theory respecting their [the poles'] elongation. 1797M. Baillie Morb. Anat. (1807) 299 If these elongations were to be situated at a distance from the neck of the bladder. 1813H. & J. Smith Rej. Addr. 61 But when on this boarded elongation it falls to my lot to say a good thing. 1837Whewell Hist. Induct. Sc. (1857) II. 282 The elongation of the image. 1869J. Martineau Ess. II. 76 His morality..is a mere elongation of law.
6. Mech. In mechanical testing, the amount of extension of a test piece when stressed, usu. expressed as a percentage of the original length; also attrib.
1866Engineering 19 Jan. 33/2 The elongation of homogeneous metal and steel is only 1/16600th part of its length for every ton of direct tensile strength per square inch. 1877Encycl. Brit. VII. 818/1 Eight different specimens..bore from 43½ to 46 lb. (average 45·2) just before breaking, with elongations of from 17 per cent to 22 per cent. a1884Knight Dict. Mech. Suppl. 868/2 The index needle also moves two slides which show the maximum of elongation or compression. 1909Cent. Dict. Suppl., Elongation strain, the percentage of elongation of a piece of material being tested in a testing-machine. 1922Glazebrook Dict. Appl. Physics I. 144/1 The elongation and contraction of area are required in order to obtain a measure of the ductility of the material. 1930Engineering 3 Jan. 31/2 The percentage elongation observed for arsenical copper was 58 per cent. |