Page:Dictionary of aviation.djvu/98

 74 DICTIONARY OF AVIATION

cyclonal ,sai'kLOO-nl, 'sai-kz-3-nl adj. of, pertaining to, or of the nature of a cyclone; cyclonic.

cyclonal gradient, see under gradient. cyclone 'sai,kLon n.

1. any storm or atmosferic disturbance in ujhich the wind has a circular, whirling, or rotatory motion, as a hurricane or tornado of limited diameter and destuctiv violence; a ternado.

2. a system of winds or atmosferic currents, often ex- tending over an area having a diameter of several hundred miles and rotating round a center of minimum barometric pressure and relativ calm which itself usually has a tr,ans- latory motion.

land cyclone, a cyclone or cyclonic system of winds which is located over a land surface.

ocean cyclone, a cyclone or cyclonic system of winds which is located over the ocean.

polar cyclone, the hypothetic cyclone in the north or the south polar region of the earth; the supposed system of ro- tatory atmosfenc currents, with cold a center, from which the lower air flows outward and the upper air flows inward.

cyclone-center 'sai-kLon,sentaz n. the center of a cyclone or area of low barometric pressure.

cyclone-flood 'sai-kLon,f;LAd n. the flood accompanying a cyclone, due to the wave of water formd by the storm; a sterm^wave.

cyclone-path, 'sai-kz,on,pa:0 n. the path or route along tuhich a cyclone moves.

cyclone-pit 'sai-ki^on/pit n. a pit or underground room made for refuge from a tornado or cyclone.

cyclone-wave 'sai-kton/weev n. the wave of water pro- duced by a cyclone.

cyclonic ^ai'ktonik adj. of or pertaining to a cyclone or cy- clones; of the nature of a cyclone.

��damp daemp v.

1. tr. depress, diminish, lower, deden : as, to *damp out the amplitude of fugoid waves.

2. intr. become deprest or lowerd; diminish, decrease. danger-zone 'deen-ds^zoon n. a zone or region of danger,

as about the cusp of a plotted fugoid or flightecurv. dart da:zt n. a pointed missil. thrown by the hand; a light spear or javelin; also, an arrow.

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