contrail

n. vapor trail of an aircraft

Contrails or vapor trails are condensation trails and artificial cirrus clouds made by the exhaust of aircraft engines or wingtip vortices which precipitate a stream of tiny ice crystals in moist, frigid upper air. Being composed of water, the visible white streams are not, in and of themselves, air pollution. However, contrails generated by engine exhaust are inevitably linked with typical fuel combustion pollutants.
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Noun
1. an artificial cloud created by an aircraft; caused either by condensation due to the reduction in air pressure above the wing surface or by water vapor in the engine exhaust
(synonym) condensation trail
(hypernym) cloud

SCIA DI CONDENSAZIONE [AEREI]

Eng: contrail
Urdu: تکاثفی دُنبالہ ۔ جم لکیر ۔ دیکھائی دینے والی مُنجمد نمی کی لکیر جو ہوائی جہاز کے گزرنے سے پیدا ہوتی ہے ۔