Page:Dictionary of aviation.djvu/273

 DICTIONARY OF AVIATION 249

2. tr. move quickly with a whizzing or buzzing sound: as, the hummingbird *whirs its wings.

whir WB:Z n. a swishing or buzzing sound, as of the wings of certain birds when in flight, or of the blades of a re- volving propeller.

whirl ws:zJ v.

1. tr. swing or turn rapidly round; rotate; revelv.

2. intr. turn swiftly round, as in a heliceid course; rotate rapidly.

whirl wB'.zl n.

1. a rapid turning or circling movement; a stuift or ro- tary motion or gyration : as, his spiral *whirl thru the air.

2. a mass of air or other matter having such a circling or heliceid motion, as an airseddy or whirlwind.

whirlblast 'wB:zl,bla:st n. a whirling blast of wind; a whirl- wind.

whirling-fan 'wB:z-!irj,f3en n. a fan which by whirling im- parts motion to an aircraft; a f an-propeller ; an air-screw.

whirling-machine 'wB:z-lir)-ma,$iin n. a primitiv ferm of whirling^table, said to have been first used by Rebbins in 1761.

whirling-table 'w8:z-lin,tee-b3l n. a machine consisting of a horizontal arm turning upon a vertical axis used for whirling or revolving planes or aerofoils in order to de- termin the resistance offerd by the air, or for determining the constants of anemometers, or for similar purposes; a whirling^machine of modern construction.

whirlwind 'wsrzl/wmd. a wind moving in a whirl, eddy, or circumscribed circular path; a mass of air, as in a tor- nado, waterspout, or sand-pillar, of which the height is usu- ally great in proportion to the width, rotating rapidly en a vertical or slightly inclined axis and having at the same time a tjanslatory motion over the land or sea.

wicker 'wikaz n. a small pliant twig; an osier; a withe; also, wickerwork.

wicker-work 'wiksz/vsnsrzk n. [also spelt wicker-work] bas- ketwork of any sort, as that of a balloon-car; anything plated, woven, or wattled of flexible and tough material, as osier, rattan, or thin strips of wood.

winch wmt$ n. a machine in which an axis is rotated by means of a crank-handle, used for winding up or letting out the holding-rope of a captiv balloon, or a kite-line; a windlass.

winch-house 'wint$,haos n. a house or bilding from which a kite-winch is workt.

wind wind n. air in natural motion at or above the earth's

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