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▪ I. lever, n.1 (ˈliːvə(r), U.S. ˈlɛ-) Forms: 3 levere, 4 levor, 4–5 levour, 6–8 leaver, 5–lever. [ME. levere, levour, a. OF. *levere, leveour (F. leveur), agent-n. f. lever to raise; in the sense ‘lever’ recorded only once (1487) as leveur; the usual Fr. word is levier (recorded from 12th c.) formed on the same vb. with different suffix; leviere fem. occurs in the 14th c.] 1. a. A bar of iron or wood serving to ‘prize up’ or dislodge from its position some heavy or firmly fixed object; a crowbar, handspike, or the like. In mod. use, this sense is more or less coloured by the scientific sense 2, which is alone formally recognized by Johnson.
1297R. Glouc. (Rolls) 3103 Hii..cables vette ynowe & laddren, & leuours & uaste ssoue & drowe. 13..Coer de L. 1935 Ever men bare them up with levours. 1382Wyclif Isa. xxvii. 1 In that dai visiten shal the Lord..vp on leuyathan, an eddere, a leuour [Vulg. serpentem vectem]. 1433Lydg. St. Edmund iii. 1202 Oon with a leuour to leffte the doore on barre. 1481Caxton Godfrey clxxx. 265 Other had grete leuers and plente of ropes and Cordes. 1553T. Wilson Rhet. (1580) 223 An other speakes, as though his woordes had neede to bee heaved out with leavers. 1642Fuller Holy & Prof. St. ii. xxiii. 147 Surely so heavy a log needed more levers than one. 1697Potter Antiq. Greece iii. xx. (1715) 148 The heavy Ship into the Sea they thrust With Leavers. 1736Butler Anal. i. i. 36 As carriages and leavers and scaffolds are in architecture. 1813Scott Rokeby i. vi, Then clanking chains and levers tell, That o'er the moat the draw-bridge fell. a1825Forby Voc. E. Anglia, Lewer, lower, a lever. 1881S. H. Hodgson Outcast Ess. 402 (Hor. Od. iii. xxvi) The lever, the bright torch, the bow, For laying doors and warders low. fig.1831Society I. 230 Jealousy is a potent lever for quickening love. 1855Motley Dutch Rep. (1861) II. 433 The new religion was only a lever by which a few artful demagogues had attempted to overthrow the King's authority. †b. gen. A bar, pole, or rod. Obs.
1297R. Glouc. (Rolls) 2680 Eldol erl of gloucestre..Hente an stronge leuour. c1320Sir Beues 1861 (MS. A) He tok a leuour in is hond, And forth to the gate he wond. c1400Ywaine & Gaw. 2386 The geant..bar a levor of yren ful strang. c1530Ld. Berners Arth. Lyt. Bryt. (1814) 366 Gonemar helde in bothe hys handes a gret leuer, wherwith he layd on amonge those knyghtes. 1609Bible (Douay) Numb. xiii. 24 They cutte of a branch with the grapes therof, which two men carried upon a leaver. 1613Purchas Pilgrimage (1614) 504 Fish-shells..so great that two strong men with a leaver can scarse draw one of them after them. 2. Mechanics. Adopted as the name for that type of ‘simple machine’ which is exemplified in the ‘lever’ (sense 1). It consists of a rigid structure of any shape (a straight bar being the normal form), fixed at one point called the fulcrum, and acted on at two other points by two forces, tending to cause it to rotate in opposite directions round the fulcrum. The force which is regarded as intended to be resisted by the use of the lever is called the weight, and the force which is applied for this purpose is called the power. Levers are said to be of the first, second, or third kind or order according as the fulcrum, the weight, or the power is in the midmost position of the three.
1648Wilkins Math. Mag. i. iv. 20 The second Mechanical faculty is the Lever. 1710J. Clarke Rohault's Nat. Phil. (1729) I. 43 Two Bodies hung at the Ends of a Balance or Leaver. 1803J. Wood Princ. Mech. iv. 50 The Lever is an inflexible rod, moveable upon a point which is called the fulcrum. 1812–16Playfair Nat. Phil. (1819) I. 117 Let A and B be two given weights, applied to the ends of the arms of a lever. 1829Nat. Philos., Mechanics ii. iii. §13. 6 (U.K.S.) If the power be in the middle, it is a lever of the third kind. 1837Whewell Hist. Induct. Sci. (1857) I. 186 Archimedes had established the doctrine of the lever. 1841T. R. Jones Anim. Kingd. 168 The levers attached to the jaws are five long and slender processes. 1851Carpenter Man. Phys. (ed. 2) 172 The hard envelopes..serve, like the bones of the Vertebrata, as levers by which the motor powers of the muscles are more advantageously employed. 3. Special applications. a. A roof-beam of naturally curved timber, forming one of the couples or principals supporting the roof (obs. exc. dial.). b. Steam-engine. † (a) = beam n.1 11 (obs.); (b) a starting-bar. c. The piece by which the barrel of a breech-loader is opened. d. In Dentistry and Surgery = elevator 2. In Midwifery = vectis (Syd. Soc. Lex.). e. The first row of a fishing-net. f. Short for lever-watch. a.1481–2in Charters Finchale (Surtees) p. ccclv, Pro..meremio empto pro j lever in tenemento Roberti Jakson. b.1758Fitzgerald in Phil. Trans. L. 727 The lever of the fire-engine [i.e. steam-engine] works up and down alternately. 1836L. Hebert Engin. & Mech. Encycl. II. 702 The attendant pushes the handle or lever which he holds. c.1881[see lever-pin]. d.1846F. Brittan tr. Malgaigne's Man. Oper. Surg. 74 With the Lever.—Its extremity is passed between two teeth, a sound and the decayed one, or a sound one and a stump. e.1884J. Paton in Encycl. Brit. XVII. 359/1. f.1865N. & Q. 27 Jan. 27/2 (Advt.), The prettiest gift for a lady is one of Jones's gold levers at 11l 11s. 1895in N. & Q. (1941) 20 Sept. 160/1 It couldn't have been a stop watch. It was a lever. 4. attrib. and Comb. a. with sense ‘belonging to a lever’, as lever-actuation, lever-edge, lever-pin; also lever-like adj.b. with sense ‘acting as a lever, worked by a lever’, as lever-brace, lever-corkscrew, lever-drill, lever-hoist, lever-jack, lever-knife, lever-pallet, lever-pendulum, lever-press, lever-punch, lever-shears, lever-spar, lever-valve.
1889G. Findlay Eng. Railway 79 The frame..known as *lever actuation.
1860All Year Round No. 57. 162 The *lever corkscrew gave a zest to his wine.
1884F. J. Britten Watch & Clockm. 207 *Lever Edges..are polished in a swing tool.
1867J. Macgregor Voy. Alone 41 The pantry is beside them with..pepper..mustard, corkscrew, and *lever-knife for preserved meat tins.
1891Atkinson Last of Giant Killers 190 The steel point of Sir Jack's Staff was inserted beneath it, and *lever-like pressure applied.
1825J. Nicholson Operat. Mechanic 524 The centre of the *lever-pallet..is in a right line between the centre of the scape-wheel and the centre of the verge.
Ibid. 526 In Ellicott's pendulum the ball was adjustable by levers, thence called the *lever pendulum.
1881Greener Gun 263 Next turn out the *lever pin on top of lever.
1873W. Cory Lett. & Jrnls. (1897) 316 The *lever-spar of a water-lift. 5. Special combs.: lever-beam Steam-engine (see beam n.1 11); lever-board, -bridge (see quots.); lever-engine, † (a) = beam-engine (obs.); (b) = side-lever engine (1876 in Knight Dict. Mech. and in later Dicts.); lever escapement (Watchmaking), an escapement in which the connexion between the pallet and the balance is made by means of two levers, one attached to the pallets and the other to the balance staff (Britten); lever-fly, a punching machine worked by a fly-wheel and a lever; lever frame, (a) (see quot. 1950); (b) ‘in a railroad hand-car, a wooden frame shaped somewhat like a letter A, which supports the lever-shaft and lever on the platform’ (Cent. Dict.); lever-man U.S., one employed to work the levers in a railway signal-box; lever watch, a watch with a lever escapement; lever-wood, the Virginian hop-hornbeam or ironwood, Ostrya Virginica (Treas. Bot. 1866).
1824R. Stuart Hist. Steam Engine 159 As the *lever-beam was dismissed, he communicated the motion to the paddle-wheels by a rod and crank attached to the piston.
1823P. Nicholson Pract. Build. 587 *Lever-boards, a set of boards, parallel to each other, so connected together that they may be turned to any angle, for the admission of more or less air or light; or so as to lap upon each other and exclude both.
1853Sir H. Douglas Milit. Bridges 312 That which is called a *Lever Bridge is made by cutting down trees, and sinking the buts of them in the bank on each side sufficiently deep that the parts which are buried may exceed in weight those which are out of the ground.
1744Desaguliers Experim. Philos. II. 489 The *Leaver Engine, often call'd Newcomen's.
1838Penny Cycl. XII. 303/2 *Lever-escapement. 1884F. J. Britten Watch & Clockm. 141 The Lever Escapement..is generally preferred for pocket watches.
1831J. Holland Manuf. Metal I. 131 The holes..are punched in the metal by the assistance of what the boiler makers call a *lever fly.
1869Bradshaw's Railway Manual XXI. App. 116 (Advt.), Patent locking *lever frames. 1950Times Rev. Industry 21/1 All points and signals are worked from a mechanical or manual lever frame. 1955Railway Mag. May 307/2 At Stockport No. 2 signalbox, the existing mechanical lever frame has been retained. 1963Kichenside & Williams Brit. Railway Signalling vi. 74 (caption) The interior of London Bridge signal box..showing the miniature lever frame.
1901Daily News 12 Jan. 6/2 A saving..has been effected in the wages of *lever men.
1848Chambers's Inform. I. 285/2 The *lever watch is so named from the lever escapement of Mudge.
Add:[2.] b. Also, by extension, used of any projecting arm or handle (usu. in the form of a straight rigid bar) by which a mechanism is operated or adjusted, whether or not the main object is to do mechanical work.
1862Illustr. Catal. Internat. Exhib., Industr. Dept., Brit. Div. II. No. 2256, The upper ladders unship by means of shifting levers. 1904A. B. F. Young Compl. Motorist iii. 64 All that is necessary in changing gear is to move the lever which tightens a band on one of the friction drums and locks it. 1954J. Masters Bhowani Junction vii. 62 There was a lever on one handlebar to work the front brake. 1971P. Toynbee Working Life iv. 60 You slip your card into the slot and pull down the lever which punches the time on it. 1988Toronto Sun 13 Apr. 159 (caption) According to the instructions, a simple flip of a lever will enable the bike to be folded. c. fig., spec. in phr. to pull the lever and varr., to activate, experiment with, or facilitate the means or agency of making something happen.
1903Contemp. Rev. Mar. 410 The papal nuntius presses every lever and turns every screw. 1974Times 4 Apr. 14 Job satisfaction might be found by moving to a new job that gave him or her the chance to ‘pull levers and see what happens’ rather than advising other people before they pull the levers. 1976National Observer (U.S.) 30 Oct. 3/3 Jane Henry, wife of a community-college professor and mother of two, is concerned about the environment, so she will pull a lever for Carter. 1985Christian Science Monitor 8 Feb. 26/3 There have been times when the Fed pulled the normal levers to coax the economy to zig, when instead that led the economy to zag. ▪ II. † ˈlever, n.2 Obs. rare—1. [f. leve v.2 + -er1.] = believer.
c1340Cursor M. (Trin.) 18719 Þe leuer [Cott. and Gött. truand] & þe baptized boþe Shulde be saued from alle loþe. ▪ III. ‖ ˈlever, n.3 Obs. rare—1. [Fr.: see levee n.2] = levee n.2 2.
1742Miss Robinson in Mrs. Delany's Lett. (1861) II. 191 We do not appear at Phœbus's Levér. ▪ IV. lever, v.|ˈliːvə(r)| [f. lever n.1] 1. a. intr. To apply a lever; to work with a lever.
1856Kane Arct. Expl. II. ii. 31 It was all in vain that Hans and I..lifted, levered, twisted and pulled. 1897Daily News 16 Mar. 6/5 They delved, and levered, and sweated. b. To make way by leverage.
1883S. Baring-Gould John Herring I. i. 9 When he took his weight off,..the plough levered out of the ground. 2. trans. a. To lift, push, or otherwise move with or as with a lever; also with along, away, out, over, up. Also refl. with into. b. To bring into a specified condition by applying a lever.
1876Preece & Sivewright Telegraphy 209 The bottom of the pole being ‘levered’ out of the ground. 1882Jefferies Bevis I. i. 11 He began to lever the raft along. 1887Baring-Gould Gaverocks I. vi. 89, I flung with such force that I levered the boat away. 1891M. M. Dowie Girl in Karp. vi. 75, I levered up an eyelid with difficulty. 1896Daily Chron. 15 Aug. 9/3 On no account should the canoe be levered with one end of the pole on the ground. 1898Daily News 19 May 5/3 The concrete fell..and levered the pier over. 1898Cycling 77 By passing a bar through the frame..and levering it straight. fig.1890Graphic 11 Oct. 406/1 He seeks this by levering out of his place his best friend. 1910Westm. Gaz. 24 Mar. 2/3 The Moderates have levered themselves into a position they have no claim to occupy on the Council. Hence ˈlevering vbl. n. Also attrib.
1869Mrs. Whitney We Girls x. (1878) 174 A few more vigorous strokes, and a little smart levering, and the nails loosened. 1897Daily News 3 Nov. 6/6 Snapped off by means of some powerful levering tool. ▪ V. lever obs. f. liver n., liver v., to deliver. ▪ VI. lever obs. var. liever, comparative of lief a. |