Cloud  —n. 1 visible mass of condensed watery vapour floating high above the ground. 2 mass of smoke or dust. 3 (foll. By of) mass of insects etc. Moving together. 4 state of gloom, trouble, or suspicion. —v. 1 cover or darken with clouds or gloom or trouble. 2 (often foll. By over, up) become overcast or gloomy. 3 make unclear.  on cloud nine colloq. Extremely happy. Under a cloud out of favour, under suspicion. With one's head in the clouds day-dreaming.  cloudless adj. [old english]