| 释义 |
watershed1|ˈwɔːtəʃɛd|
[f. water n. + shed n.1
The equivalent G. wasserscheide has been in use from the 14th c. As a scientific term, it became common about 1800. The Eng. word, which first appears about the same date, was perh. formed in imitation of the Ger. synonym.]
1. The line separating the waters flowing into different rivers or river basins; a narrow elevated tract of ground between two drainage areas: = water-parting.
1803Prize Ess. Highl. Soc. Scot. II. 20 Strathcluony..is a very high inland tract, being the water-shed of the country between the two seas. 1830Lyell Princ. Geol. I. 175 The College, a small stream which flows at a moderate declivity from the eastern water-shed of the Cheviot-Hills. 1845Darwin Voy. Nat. xix. (1852) 442 The line of Water-shed which divides the inland streams from those on the coast, has a height of 3000 feet. 1850Times 16 Nov. 5/2 In order to satisfy themselves as to the amount of supply furnished by the sources in question, the Board of Health deputed Mr. Rammell to survey the various lines of watershed. 1859H. Kingsley G. Hamlyn vi, He was crossing the highest water⁓shed in the county by an open, low-sided valley. 1863Lyell Antiq. Man xv. 297 We should also remember that the crests or watersheds of the Alps and Jura are about eighty miles apart. 1880Geikie Phys. Geog. iv. 257 The water⁓shed of a country or continent is thus a line which divides the flow of the brooks and rivers on two opposite slopes.
b. fig. Also attrib.
1878Longfellow Kéramos i. 87 Midnight! the outpost of advancing day!.. The watershed of Time, from which the streams of Yesterday and To-morrow take their way. 1884R. F. Burton Bk. Sword viii. 150 note, Hence, too, the superficial observation that the Afghans..are Jews because they have the typical Jewish look. The reason is that they are derived from the same ethnic centre, a great watershed of race. 1886Symonds Renaiss. It., Cath. React. (1898) VII. 208 A watershed of time between the Renaissance and the Counter-Reformation. 1893Nation (N.Y.) 3 Aug. 87/1 That resolution marks the water-shed of our Revolutionary politics. 1962B.B.C. Handbk. 32 The BBC's Code of Practice on Violence, its new 9.30 p.m. watershed policy, its intention to distinguish those programmes which it thinks unsuitable, and perhaps more important, suitable for children..show that both sides are aware of the problem. 1973T. Tobin Lett. G. Ade 2 While a journalist in Chicago, Ade became one of the more astute chroniclers of the daily preoccupations of ordinary people who were living through the ‘watershed period’. 1980Listener 29 May 68/3 On the Town, which [Gene] Kelly himself describes as a watershed picture, and which opened up the musical to location shooting.
2. loosely.
a. The slope down which the water flows from a water-parting.
1839Murchison Silur. Syst. i. xxxvii. 512 To the south⁓west of Kington the lower beds of the Old Red Sandstone..have been the sub-aqueous water-shed, down which the coarse detritus has been swept. 1877Huxley Physiogr. 18 To avoid all ambiguity it is perhaps best to set aside the original meaning of ‘watershed’, and employ the term to denote the slope along which the water flows, while the expression ‘water-parting’ is employed for the summit of this slope.
b. The whole gathering ground of a river system.
1874E. Coues Birds N.W. Introd. p. vii, The Missouri Region, in its broadest sense, as embracing the whole water⁓shed of that great river and its tributaries. 1880Webster Suppl., Water-shed. 2. The country or basin drained by any stream of water and its tributaries. 1913White Catskill Water Supply of N.Y. 17 The Croton watershed would in a few years be drawn on to its full capacity.
3. [? Associated with shed v.1 4 d.] A structure for throwing off water.
1881R. G. White Eng. Without & Within xiv. 319 The great wheel caught my umbrella, which was twisted out of my hand in a twinkling... I picked up my wounded water⁓shed, and returned with it to Burlington Arcade. 1886Trans. R. Inst. Brit. Archit. II. 79 Nothing indicates the nature of the water-shed. It may have been some description of thatch; but more probably I think of wood shingle. 1898Scribner's Mag. Oct. 503/1 A water-shed to throw the water away from the forecastle hatch was built. |