| 释义 |
▪ I. duct, n.|dʌkt|
[ad. L. duct-us leading, conduct, command, in med.L. aqueduct, n. of action f. dūcĕre to lead, conduct, draw; in mod.L. in sense 6. The L. form was formerly in Eng. use.]
†1. The action of leading; lead, guidance. Obs.
a1660Hammond (J.), To obey our fate, to follow the duct of the stars. 1684tr. Bonet's Merc. Compit. vi. 216 The Physician..is bound to follow Nature's duct.
†2. Course, direction, trend. Obs.
1650Bulwer Anthropomet. 48 The other the ductus or course of the hair turns away. 1662Glanvill Lux Orient. 146 (T.) According to the duct of this hypothesis. 1712Blair in Phil. Trans. XXVII. 435 Observing..the Duct of its Fibres. 1718J. Chamberlayne Relig. Philos. I. ix. §8 Remarks upon each Duct, or Course, of these Nerves.
†3. A passage, etc. leading in any direction. Obs.
1670E. Brown in Phil. Trans. V. 1191 The ductus's or veins of Metals, do..some-times run North and South. a1711Ken Anodynes Poet. Wks. 1721 III. 431, I then meet labyrinthal Ducts, Turnings and Windings, dark Retreats.
4. A stroke drawn or traced, or the manner of tracing it (cf. L. ductus litterarum).
1699N. Marsh in Lett. Lit. Men (Camden) 297 Using..a magnifying glass for discovering the more diminutive lines, ductuses, and appendages to the Letters. 1760Swinton in Phil. Trans. LI. 857 The ducts of the letters are drawn with so much accuracy, that they may be intirely depended upon. 1796Pegge Anonym. (1809) 278 The ducts of the letters will sufficiently justify this reading. 1954N. Denholm-Young Handwriting iv. 32 The method of tracing the strokes, and the resulting general appearance of the script can conveniently be termed the duct or ductus. 1957N. R. Ker Catal. MSS. containing Anglo-Saxon p. xxv, The change from Anglo-Saxon minuscule to caroline minuscule..involved the duct of the handwriting of all manuscripts. 1969M. B. Parkes Eng. Cursive Book Hands 1250–1500 p. xxvi, The duct of a hand is the distinctive manner in which strokes are traced upon the writing surface: it represents the combination of such factors as the angle at which the pen was held in relation to the way in which it was cut, the degree of pressure applied to it, and the direction in which it was moved.
5. a. A conduit, channel, or tube, for the conveyance of water or other liquid. spec. = ink-trough; also attrib.
1713Pope Guardian No. 173 ⁋7 The two fountains..were brought by conduits or ducts. 1776Act 16 Geo. III, c. 56 (T.) For making and perfecting any channel, course, main cut, or duct, through any of the grounds. 1809A. Henry Trav. 69 The [sugar-maple] trees were..tapped, and spouts or ducts introduced into the wound. 1880Print. Trades Jrnl. No. 31. 10 For letterpress it has two ink ducts. 1888Encycl. Brit. XXIII. 706/1 A trough, which contains the ink..is fitted with the duct roller of cast iron. 1968Gloss. Terms Offset Lithogr. Printing (B.S.I.) 38 Duct, the trough..which contains the supply of ink, and by means of which the ink is presented to the duct roller.
b. A pipe or tube through which air is conveyed for cooling, ventilation, etc.
1884J. S. Billings Princ. Ventilation & Heating xi. 190 Into this chimney empties a foul-air duct..which receives the air from lateral ducts opening beneath the foot of each bed. 1908A. G. King Pract. Steam & Hot Water Heating ix. 92 It is well to take the hot-air duct from the boxing at the end opposite to that where the cold air enters. 1930Engineering 28 Feb. 279/1 The arrangement of the fans and ducts. 1947T. N. Adlam Radiant Heating xiv. 308 For circulating the air through the various offices..a system of metal ducts has been installed. 1962Which? (Car Suppl.) Oct. 139/1 Demister duct trim screws [were] slack.
c. A conduit for an electric cable or the like.
1893T. O'C. Sloane Stand. Electr. Dict. 193 Duct, the tube or compartment in an electric subway for the reception of a cable. 1901Westm. Gaz. 11 Apr. 7/2 The work of laying the cable ducts has practically finished. 1945‘Electr. Engineer’ Ref. Bk. xxvi. 7 The lightest and most convenient system is probably to run the cables in open ducts. 1962P. Dunsheath Hist. Electr. Eng. xiv. 241 The [telephone] cables were at first drawn into cast-iron pipes and later earthenware single and multiple ducts.
6. a. Phys. A tube or canal in the animal body, by which the bodily fluids are conveyed. Formerly used in a wide sense, so as to include the blood-vessels and alimentary canal, but now applied more strictly to the vessels conveying the chyle, lymph, and secretions. Also used attrib. in such phrases as duct-cancer, duct-cyst, duct-papilloma, = (cancer, etc.) affecting the epithelium of the ducts of the mammary glands.
These have names expressing their position or character, or in some cases the name of their discoverer, as biliary, choledoch, cystic, efferent, genito-urinary, hepatic, lactiferous, lymphatic, nasal, pancreatic, parotid, thoracic duct. (See these words.) Also ducts of Bellini, the excretory tubes of the kidneys; duct of Bartholin, ducts of Rivinus, certain ducts of the sublingual gland; Steno's duct, that of the parotid gland, which conveys saliva into the mouth; Wharton's duct, that of the submaxillary gland, also conveying saliva; duct of Wirsung, the principal pancreatic duct; Wolffian duct, the excretory duct of the Wolffian body or primitive kidney.
1667Phil. Trans. II. 579 There being peculiar ductus's, by which the bloud passeth into the Aorta. 1692Bentley Boyle Lect. 109 All the various ducts and ventricles of the body. 1741Monro Anat. (ed. 3) 134 Steno's Duct may be traced some Way on the Side of these Passages next the Nose. 1748Hartley Observ. Man i. ii. 151 The whole alimentary Duct, quite down to the Anus. 1767Gooch Treat. Wounds I. 327 marg., The treatment of wounds of the salival ducts. 1837–9Hallam Hist. Lit. (1847) III. 219 Eustachius had observed the thoracic duct in a horse. 1845–6G. E. Day tr. Simon's Anim. Chem. I. 210 The capillary system surrounding the biliary ducts. 1864T. Holmes Syst. Surg. IV. 680 Duct-cysts. Perfectly closed cysts..but having an opening communicating with a duct. 1872Huxley Phys. v. 131 The neck by which a gland communicates with the free surface is called its duct. 1889Lancet 21 Dec. 1278/1 In duct cancer of the breast he had not observed eczematous appearances. 1910Practitioner Apr. 469 When a duct-papilloma obstructs one of the large ducts near the nipple. 1966Wright & Symmers Systemic Path. I. xxviii. 982/2 Duct papilloma is considerably less frequent than fibroadenoma.
b. Bot. One of the vessels of the vascular tissue of plants, formed by a row of cells of which the partitions have been obliterated, and containing air, water, or some secretion; spec. the narrow tubular continuous cells surrounding the broad cells or utricles in the leaves of Sphagnum.
1858Carpenter Veg. Phys. §40 The midrib and veins..consist of three kinds of structure;—ducts or canals, which are supposed to transmit fluid. 1866Treas. Bot. I. 433/1 Ducts, tubular vessels marked by transverse lines or dots.
▸ duct tape n.perhaps an alteration of earlier duck tape n. at duck n.3 Additions orig. N. Amer. a strong cloth-backed waterproof adhesive tape, originally used for sealing joints in heating and ventilation ducts, and (later) for holding electrical cables securely in place, now in widespread general use esp. to repair, secure, or connect a range of appliances, fixtures, and equipment; cf. gaffer tape n. at gaffer n. Additions.
1965Sheboygan (Wisconsin) Press 29 Sept. 32/8 (advt.) Now! A Complete Line Of Tapes At Lowest Prices. Used In The Home, Shop, Office and School. Masking Tape... Cloth *Duct Tape... Weatherstripping Tape. 1973Air Conditioning, Heating & Refrig. News 19 Nov. 17/5 (heading) What's New... Duct tape... Type 96T waterproof, flame retardant cloth tape, which offers adhesion of 50 oz./in., is recommended for duct-work... The tape is constructed of polyethylene film laminated to flame retardant cotton fabric. 1998On the Edge May 41/1 Duct tape can be used to fix a 'biner or hook to the end and the lead rope can be run through it prior to extension.
▪ II. duct, v.|dʌkt|
[f. the n.]
trans. To convey through a duct; usu. in the form ducted ppl. a., conveyed through a duct; situated or operating in a duct. Cf. ducting vbl. n.
1936Aircraft Engin. VIII. 218/3 The ideal efficiency of the ducted radiator at high speed is about 50 per cent greater. 1938Encycl. Brit. Bk. of Yr. 20/2 Ducted cooling has been developed sufficiently to recover..more than one half of the radiator losses. 1945Jrnl. R. Aeronaut. Soc. XLIX. 698/1 The ducted fan system of propulsion, as we understand it to-day, consists of a fairly large diameter ducted fan or axial compressor of relatively low compression ratio at the intake to the nacelle. 1945‘Electr. Engineer’ Ref. Bk. xxvi. 7 Ducted cables are screened by the metal box in which they run. 1958Times Rev. Industry Aug. 39/1 Compressed air is ducted from the compressors..to..pressure jets. 1965Economist 13 Feb. 670/3 A revolutionary new type of helicopter which uses hot ducted turbine exhaust gases to drive the rotor blades through tip vents. |