| 释义 |
perimeter|pəˈrɪmɪtə(r)|
[ad. L. perimetros, a. Gr. περίµετρος circumference, f. περί around + µέτρον measure: cf. It. perimetro (Florio 1611), F. périmètre (1541 in Hatz.-Darm.).]
1. a. The continuous line or lines forming the boundary of a closed geometrical figure (curved or rectilineal), or of any area or surface; circumference, periphery, outline; also, the measure or length of the circumference. (Cf. diameter 1, 2.)
1592R. D. Hypnerotomachia 22 b, The Stilliced or Perimeter, or vpper part of the vppermost Coronice. 1620T. Granger Div. Logike 173 A perimeter, which is the circuite, or compasse of a figure. 1696Whiston The. Earth i. (1722) 21 Of all Figures, whose Perimeters are equal, the Circle is the most capacious. 1776Kentish Trav. Comp. 327 In less than three months, the whole perimeter..or inclusion of the harbour, was finished. 1840Lardner Geom. 100 The perimeter of the polygon will continually approach to coincidence with the circumference of the circle in which it is inscribed. 1881Casey Sequel to Euclid 16.
fig.1632B. Jonson Magn. Lady Induct., He makes that his centre attractive to draw thither a diversity of guests, all persons of different humours to make up his perimeter.
†b. Applied to a space surrounding something.
1641Milton Ch. Govt. ii. iii. (1851) 168 In respect of a woodden table and the perimeter of holy ground about it..the Priest esteems their lay-ships unhallow'd and unclean.
c. Mil. A defended boundary of a troop position. Also transf., the boundary of an airfield or civil airport.
1943J. Duffy Australians in Malaya 41 Possibly this was true of an attack from the sea, but on the northern perimeter were no adequate defences. 1958Spectator 11 July 52/3 I can tell you what really happened in the fighting round the perimeter. 1967Boston Herald 1 Apr. 14/6 The enemy opened up with mortar and howitzer fire, hitting American troops who had pulled back into defensive perimeters. 1974Guardian 1 Aug. 1/7 Soldiers..moved on to the airport perimeter. 1977Times 9 Sept. 15/7 After six hours without food in a plane on the perimeter at Heathrow the flight was cancelled.
2. An instrument for measuring the field of vision and determining the visual powers of different parts of the retina.
1875H. Walton Dis. Eye 1070 The perimeter brought out by C. C. Jeaffreson, seems to be the best. 1899Allbutt's Syst. Med. VI. 846 Their precise determination and localisation require the assistance of the perimeter.
attrib.1889G. A. Berry Dis. Eye 553 The result of a perimeter examination..recorded on a chart.
3. attrib. and Comb., as (sense 1 c) perimeter fence, perimeter road; perimeter track, a runway round an airfield. See also sense 2.
1974A. Price Other Paths to Glory iii. i. 249 Soldiers..patrolling the perimeter fence. 1976Scottish Daily Express 27 Dec. 1/2 Two wolves were shot dead only yards from the perimeter fence by zoo director Roger Wheater.
1974Times 7 Jan. 1/4 There were five road blocks of troops and police on the airport perimeter road where it passes close to runways.
1946Happy Landings (Air Ministry) July 10/1 The Spitfire was taxying out for take-off, along the perimeter track. 1959J. L. Nayler Dict. Aeronaut. Engin. 187 Perimeter track, a taxi track round the perimeter of an airfield for the use of aircraft and motor vehicles.
Hence peˈrimeterless a.
1849Tait's Mag. XVI. 380 Illimitable, perimeterless, immutable space. |