storm-cloud
n
(a) large black cloud coming with a storm or indicating that a storm is likely to happen 暴風云(暴風雨時出現的或預示暴風雨將至的濃密的烏云).
(b) (usu pl 通常作復數) (fig 比喻) sign of sth dangerousor threatening 危險的跡象; 兇兆
storm-clouds of war gathering over Europe 籠罩著歐洲上空的戰爭烏云.