Толковый словарь английского языка Oxford English Reference - volatile

adj. & n. --adj. 1 evaporating rapidly (volatile salts). 2 changeable, fickle. 3 lively, light-hearted. 4 apt to break out into violence. 5 transient. --n. a volatile substance. Phrases and idioms volatile oil = essential oil. Derivatives volatileness n. volatility n. Etymology: OF volatil or L volatilis f. volare volat- fly