| 释义 |
▪ I. overfall, n.|ˈəʊvəfɔːl|
[over- 5, 6.]
1. Naut. A turbulent surface of water with short breaking waves, caused by a strong current or tide setting over a submarine ridge or shoal, or by the meeting of contrary currents. Also transf. and fig.
1542Udall Erasm. Apoph. 119 b, A daungerous goulfe, makyng sore ouerfalles by reason of the meetyng of soondry streames in one pointe. 1599Hakluyt Voy. II. ii. 36 Certaine Currants, which did set to the West Southwestward so fast as if it had bene the ouerfall of a sand, making a great noyse like vnto a streame or tide-gate when the water is shoale. 1633T. James Voy. 40 We..came amongst many strange races, and ouer-falles. 1726G. Shelvocke Voy. round World 386 The frightful riplings and over-falls of the water. 1748Anson's Voy. iii. ii. 315 This tide runs at first with a vast head and overfall of water. 1774M. Mackenzie Maritime Surv. Plate iv, Overfalls; or rough, breaking Seas. 1867J. Macgregor Voy. Alone (1868) 75 All over the British Channel there are patches of sand, shingle, or rock..even without any wind they cause the tide-stream to rush over them in great eddies and confused bubbling waves... These places are called..in some charts overfalls. 1947A. C. Douglas Gliding & Advanced Soaring i. 32 The cloud currents, the heat turbulence, high winds and mountain overfalls, which the aeroplane pilot finds so unpleasant or even dangerous, are regarded by the sail⁓plane pilot as friends, not as enemies. 1961B. Fergusson Watery Maze iv. 89 Radiating in every direction from C.O.H.Q. were heavy overfalls, as they are called in seaman's parlance, or troubled waters, in landsmen's, needing more than a modicum of oil. 1970Motor Boat & Yachting 16 Oct. 35/1 We didn't bother to avoid an area marked on the large scale chart with those squiggly lines that denote dangerous overfalls. 1975J. R. L. Anderson Death in North Sea viii. 139 There were two main tidal streams... They might run up to about two knots, with a somewhat faster rate by some overfalls off Spurn Head.
2. A sudden drop in the sea-bottom, as at the edge of a submarine terrace or ledge.
1798S. Wilcocke in Naval Chron. (1799) II. 61 It is broken ground, and overfalls of about half a fathom, every cast of the lead. 1804A. Duncan Mariner's Chron. I. 300, I heard that he had very great overfalls, from twenty seven to thirteen fathoms at one cast, when he was standing in the bay towards the village of Felix. 1817Chron. in Ann. Reg. 562/2 The channel..is perfectly clear of shoals, but the overfalls are sudden from 15 to 21 and 12 to 7 fathoms. 1859R. F. Burton Centr. Afr. in Jrnl. Geog. Soc. XXIX. 236 The shingly shore shelves rapidly, without steps or overfalls, into blue water.
3. A waterfall in a river, a cataract or rapid.
1596Raleigh Discov. Gviana 67 Marched ouer land to view the strange ouerfals of the riuer of Caroli, which rored so farre of... There appeared some ten or twelve ouerfals in sight, every one as high ouer the other as a Church tower. 1600J. Pory tr. Leo's Africa Introd. 44 It is reported that Nilus doth the like at his Cataracts or ouerfals. 1613Voy. Guiana in Harl. Misc. (Malh.) III. 195, I travelled up the river of Wiapoco, to view the overfalls. 1811D. Buchan in K. Winter Shananditti (1975) ii. 24 This day's distance is estimated at eleven miles allowing seven from the island..up to the overfall. 1921H. Guthrie-Smith Tutira i. 5 A meandering serpentine creek..which..breaks into a series of overfalls.
4. A structure to allow the overflow of water from a canal or a lock on a river, when the water reaches a certain level. (Also used to keep the water up to the required level.)
1791W. Jessop Rep. River Witham 15 Culverts and Overfalls, {pstlg}90. 1805Z. Allnutt Navig. Thames 22 The new constructed open Weir at Windsor,..it will be perceived how trifling..stop or pen, it can possibly make when the moveable Gates, Overfalls, and Rimers are taken away. 1829Southey Inscript. Caled. Canal 2 in Anniversary 196 [Thou hast seen] the rivulet Admitted by its intake peaceably, Forthwith by gentle overfall discharged. 1846Kane tr. Rühlman on Turbines 23 In the watercourse,..is to be built up a partition of boards, or, as it is termed, an overfall. 1881H. W. Taunt Thames Map 13/2 The village [Streatley], with the weirs and overfalls in the foreground.
5. Comb., as overfall-mill, a mill worked by an overshot wheel; overfall-weir, a weir which water passes over.
1615G. Sandys Trav. 127 So plentifull a streame, as able to turn an ouerfall mill. 1861Smiles Engineers II. 467 A little above it was an ancient overfall weir.
▪ II. overfall, v.|əʊvəˈfɔːl|
[OE. oferfeallan = MHG. übervallen, Ger. überfallen; MDu., Du. overvallen to attack, surprise: see over- 7, 6.]
1. trans. To fall upon or over.
c1200Ormin 4799, & tær fell dun þatt hus þurrh wind, & oferrfell hemm alle. a1425Cursor M. 16661 (Trin.) Þe hilles shul þei bidde ouerfalle vs. 1895A. Nutt Voy. Bran 190 A thick mist overfell them.
b. To fall upon, attack, assail.
971Blickl. Hom. 203 Hie..oferfeollan þa ðe þa..yrmþo ᵹenæson. 1382Wyclif Lev. xx. 27 With stonus men shulen overfalle hem. 1837Carlyle Fr. Rev. I. iii. viii. 144 Silence: which some liken to that of the Roman Senate overfallen by Brennus.
2. intr. To fall over.
[a1300E.E. Psalter lvii[i]. 9 Over fel þe fire sa bright (1382 Wyclif, fyr fel ouer). ]1530Tindale Pract. Prelates Wks. (Parker Soc.) II. 251 It cannot be chosen but that many shall overfall. 1844Mrs. Browning Duchess May xcv, Horse and riders overfell.
Hence overˈfalling vbl. n., a falling over.
18..J. Wilson Trees in Blackw. Mag., The shape being indistinct in its regular..over-fallings, and over-foldings, and over-hangings, of light and shade. |