Page:Dictionary of aviation.djvu/269

 DICTIONARY OF AVIATION 245

wave-line 'weev,lain adj. having the ferm ef, or related to, the lines or outlines of the waves in a fluid; undulating; wavy: as, a bedy molded in *wave?line curvs; a flying^ma- chine moving in an undulating or *wave*line course, com- pare streamline.

wave-surface 'weev,SBzfis n.

1. the surface of a wave or undulation in a fluid.

2. a flexible surface or aerofoil which ferms part of a flying^machine, and in which a rapid undulatory or wave motion is produced for the purpose of causing the surface to propel or sustain the craft in the air.

wave-train 'weev,treen n. a train or series of waves in a fluid; a trailing succession of undulations.

weather 'wedaer n. [also spelt wether] the state of the air or atmosfere with respect to its cloudiness, humidity, mo- tions, temperature, pressure, electrical condition, or other characteristics.

broken weather, unsettled wether.

clerk of the weather, a humorous personification of the influences controlling the wether; Old Preb; also, the di- rector of the British Meteorological Office or the meteoro- logical department of the SignakService of the United States.

falling weatlier, wether in which there is, or is liable to be, a precipitation or fall of rain, snow, or hail; rainy or snowy wether.

radiation weather, wether in which radiation of heat from the earth's surface is especially noticeable; the clear dry atmosferic condition which prevails within areas of high barometric pressure or descending air when terres- trial radiation of heat is at its maximum.

Weather-Bureau 'wed3z,bju:-zo n. a bureau of the Depart- ment of Agriculture of the United States government hav- ing charge of the forecasting of the wether, issuance of of wether^warnings, display of wether^signals, etc.

weather-card 'weo9z,ka:zd n. a card en which is a dia- gram showing the average or typical wether^conditions en each side of moving areas of high or low barometric pressure.

weather-case 'wectezjkees n. a case holding instruments for observing the wether; a cupboard containing meteorologi- cal apparatus.

weather-change 'wed3z,t$eend3 n. a change in the wether; an alteration of general atmosferic conditions.

weather-chart 'wed9z,t$a:zt n. a wether^map.

synoptic weather-chart, a synoptic chart of the wether;

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