| 释义 |
tractor|ˈtræktə(r)|
[Late or med.L. agent-n. from trahĕre, tract-um to draw: see -or.]
1. pl. (in full (Perkins's) metallic tractors): Name of a device invented by Elisha Perkins, an American physician (died 1799), consisting of a pair of pointed rods of different metals, as brass and steel, which were believed to relieve rheumatic or other pain by being drawn or rubbed over the skin: see Perkinism. Obs. exc. Hist.
1798C. C. Langworthy (title) A View of the Perkinean Electricity; or, an Inquiry into the Influence of Metallic Tractors. 1801E. Darwin Zoon. (ed. 3) II. 63 With the supposed existence of ghosts or apparitions, witchcraft, vampyrism..and American tractors, such theories..must vanish. 1825Southey Lett. (1856) III. 499 His prayers may cure just as well as tractors or animal magnetism. 1885Whittier Pr. Wks. (1889) II. 314 Jacob Perkins, in drawing out diseases with his metallic tractors, was quite as successful as modern ‘faith and mind’ doctors.
2. One who or that which draws or pulls something.
a. In general sense.
1856Kane Arct. Expl. I. 149 His limbs..splendid tractors for the sledge. 1880Daily Tel. 23 Sept., The introduction of the iron road with its steam-horse for tractor.
b. Surg. ‘An obstetric forceps’ (Knight Dict. Mech. 1877).
c. A traction-engine; a locomotive engine of any kind used for traction of loaded wagons, artillery, etc., on ordinary roads, or for drawing gang-ploughs; also, ‘the frame and steel rope by which a gang of plows is drawn across a field by a traction-engine’ (Cent. Dict. Supp.). In mod. use (now the usual sense), a rugged, powerful motor vehicle for drawing farm machinery, esp. one with large rear wheels and an elevated driving seat.
1901Daily Chron. 2 Aug. 6/4 These transformers supply the overhead trolley wires, which feed special ‘electrical tractors’ running along the towing-path, and in these tractors the drivers sit and control operations. 1902Ibid. 29 Oct. 3/4 The County Council has not yet sanctioned the use of the tractor, but it will come before the members for consideration at an early date. 1903Motor. Ann. 253 Rhodesia has appealed to motor manufacturers to supply motor-wagons or tractors for use specially in hilly country. 1905Sci. Amer. Suppl. 4 Nov. 24948/3 At the recent show of the British Royal Agricultural Society great interest was centered in the Scott motor tractor... The motor in this tractor is a 24-horse-power..standard Aster engine. 1910Sci. Amer. 15 Jan. 51/2 American motor tractors used for plowing and threshing usually develop from 12 to 35 horse-power. 1917Isle of Ely & Wisbech Advertiser 28 Nov., This Tractor will operate on any land... It maintains a firm grip without injuring the lightest surfaces. 1932[see combine n. c]. 1958Economist 11 Jan. 94/2 Antarctica's native inhabitants, on seeing the tractor marks in the snow, may well..ask themselves what will happen next. 1972R. Adams Watership Down xix. 111 Few places are far from human noise—cars, buses, motor-cycles, tractors, lorries.
d. Aeronaut. An airscrew mounted at the front of an aircraft so as to exert a pull; an aircraft having this. Usu. attrib. (see sense 4 below). Cf. pusher 2 c.
1903Work 18 Apr. 171/1 A screw..working in front and acting as a tractor. 1909[see kite n. 3 c]. 1914Sphere 7 Mar. 302/3 The Short and Sopwith tractors. 1980H. F. King Sopwith Aircraft 1912–20 20 Concerning the two early Naval Sopwith tractors, it seems worth recording that a demi-official drawing once existed showing just such a machine.
e. The driving section of an articulated lorry.
1926Encycl. Brit. II. 987/2 Another combination for heavy merchandise transportation consisted of a road tractor, which was merely a foreshortened truck chassis, and a semi-trailer. 1951[see landing-gear s.v. landing vbl. n. 8]. 1977[see prime mover 3]. 1982New Scientist 11 Nov. 339/2 A lorry that has been loaded quite legally will tend to become overloaded on the drive axle (the rear of the two axles on the tractor) if it is gradually unloaded from the rear.
f. The mechanism that draws the paper through a printer.
1970U.S. Patent 3,511,354 2 A switch is operated to reduce the speed of the tractor whenever..an excess of forms queued between the tractor and the stacker is such that a forms jam is imminent. 1983Austral. Microcomputer Mag. Sept. 88/3 The TDS-13 daisy wheel printer handles paper up to 15in wide and has variable tractors and a friction platen to accommodate both continuous forms and sheets.
3. Geom. (See quot.)
1867Cayley Math. Papers VII. 73, I use the term ‘tractor’ to denote a line which meets any given lines. Ibid., Four given lines may be directrices (generating lines) of the same hyperboloid, viz. every tractor of any three of the four lines is then a tractor of all the four lines.
4. attrib. and Comb., as (sense 2 c) tractor-driver, tractor-station; tractor-drawn, tractor-mounted adjs.; (sense 2 d) tractor aircraft, tractor airscrew, tractor biplane, tractor machine, tractor monoplane, tractor propeller, tractor screw, tractor seaplane; tractorman, one who drives a farm tractor; tractor-trailer U.S., an articulated lorry; cf. trailer-truck s.v. trailer n. 9.
1969K. Munson Pioneer Aircraft 1903–14 110/1 A very early British Breguet bore the legend ‘B. 3’ on the rudder, the prefix letter indicating a tractor aircraft.
1932Rep. & Mem. Aeronaut. Res. Committee No. 1522. 1 The magnitude of the retardation of air flow..has a mean value of 0·05 for a tractor airscrew in front of a medium body.
1912S. F. Walker Aviation iv. 28 In the later form of biplane, known as the tractor biplane, the engine and propeller are placed in front. 1969K. Munson Pioneer Aircraft 1903–14 98/1 Antoinette III was the alternative title of the Ferber IX, a tractor biplane..which was abandoned after only a few trial flights in..1908.
1943J. S. Huxley TVA 43 (caption) Terraces, like the one being thrown up by a tractor-drawn grader..retain from 85 to 90 per cent. of the rainfall. 1971Power Farming Mar. 57/1 The machine is tractor-drawn.
1945H. J. Massingham Wisdom of Fields x. 208 The tractor-driver despises the hard work of the older countryman and soon..he will need an elevator to lift him on his seat. 1969R. Blythe Akenfield 17 Most modern farms need..a good tractor-driver or two, as once they needed good ploughmen.
1928C. F. S. Gamble Story North Sea Air Station iv. 67 He was then of the opinion that ‘pusher machines’ were superior to ‘tractor machines’. 1980H. F. King Sopwith Aircraft 1912–20 20 With a tractor aeroplane that was only a little faster than one of his motor⁓boats..Sopwith could hardly be content.
1946J. W. Day Harvest Adventure xiii. 210 Grover, the head tractorman. 1976Northumberland Gaz. 26 Nov., Farmers appreciate the difficulties faced by shepherds and tractormen, he said.
1960Tractor monoplane [see monoplane]. 1960Farmer & Stockbreeder 12 Jan. 83/2 Tractor-mounted rotary tiller. 1979Internat. Pest Control Nov./Dec. 139/1 Larger units to fit tractor-mounted spray booms.
1910R. Ferris How it Flies xx. 473 Tractor propeller, a propeller placed in front, so that it pulls the machine through the air, instead of pushing, or thrusting it from behind. 1910C. C. Turner Aerial Navigation of To-day viii. 127 In many monoplanes a single screw in front is used. It pulls the machine, and is often called a ‘tractor’ screw. 1969K. Munson Pioneer Aircraft 1903–14 12 A Sopwith tractor seaplane.
1958New Statesman 5 Apr. 423/2 The state is going to sell..some 20 billion roubles worth of farm machinery at present in the garages and parking lots of some 8,000 machine and tractor stations. 1965M. Michael tr. J. Myrdal's Report from Chinese Village (1967) i. 44 We hire one [tractor] from the tractor station at Yenan.
1949Tractor-trailer [see jack-knife v.]. 1977D. E. Westlake Nobody's Perfect xi. 143 A large tractor-trailer was..trying to back into position.
Hence tractoˈration, the use of metallic tractors (see 1): also allusively; ˈtractoring ppl. a., using metallic tractors; ˈtractorism = tractoration; ˈtractorist, one who uses metallic tractors; ˈtractorize v., intr. to use metallic tractors; trans. to get by tractorizing (quot. 18032); to treat with metallic tractors or similar appliances (quot. 1817); whence ˈtractorizing vbl. n. and ppl. a. (All more or less nonce-wds. and Obs.) Also (in sense 2 c) ˈtractorcade [-cade], a procession of tractors; ˈtractored ppl. a., ploughed or cultivated by tractors; ˈtractoring vbl. n., activity involving a farm tractor.
1803Fessenden (ed. 2) (title), Terrible *Tractoration! A Poetical Petition against Galvanising Trumpery, and the Perkinistic Institution. 1861O. W. Holmes Med. Ess. Pref. (1891) 9 Homœopathy has not died out so rapidly as Tractoration.
1977Detroit Free Press 11 Dec. 13-a/3 State and local police said there were no reports of traffic problems or arrests as a result of the so-called ‘*tractorcade’. 1981Observer 22 Nov. 11/1 Towns throughout Northern Ireland will be choked with ‘tractorcades’ and marches.
1966Auden About House 37 A house backed by orderly woods, Facing a *tractored sugar-beet country.
1803Fessenden Terrible Tractoration iii. xxv, And you'll confound the *tractoring folks By Haygarth's tale. 1949E. Coxhead Wind in West iii. 69 One [man] got out the tractor... When the tractoring was finished Les..got himself a fork from the byre.
1802–12Bentham Ration, Judic. Evid. V. 189 The impostures that..have been seen acted on the spiritual and medical theatres: to exorcism, animal magnetism, and *tractorism.
Ibid., The operations..of the magnetist, and *tractorist no less so, in the expulsion of non-existent diseases.
1803Fessenden (title) A Poetical Petition against *Tractorising Trumpery, and the Perkinistic Institution. Ibid. iii. viii, To tractorise away our guineas. 1817Monthly Mag. XLIII. 293 Which cures were performed..by tractorizing them with rusty nails.
▸ tractor beam n. Science Fiction a (hypothetical) beam of energy used to move or immobilize objects in space.
1931Amazing Stories Sept. 549/1 Brandon swung mighty *tractor beams upon the severed halves of the Jovian vessel. 1948Astounding Sci. Fiction Feb. 10/2 It captures three different scanner-scouts, holding them with some sort of a tractor beam, whirling them around like a stone on a string, and letting them go straight at the nearest planet. 2002Electronic Gaming Monthly Mar. 135/3 Jab the grind button anywhere near an edge..and you get yanked to it like you're caught in a tractor beam. |