n. & v.
n. 1 a visible mass of condensed watery vapour floating in the atmosphere high above the general level of the ground. 2 a mass of smoke or dust. 3 (foll. by of) a great number of insects, birds, etc., moving together. 4 a a state of gloom, trouble, or suspicion. b a frowning or depressed look (a cloud on his brow). 5 a local dimness or a vague patch of colour in or on a liquid or a transparent body. 6 an unsubstantial or fleeting thing. 7 obscurity.
v. 1 tr. cover or darken with clouds or gloom or trouble. 2 intr. (often foll. by over, up) become overcast or gloomy. 3 tr. make unclear. 4 tr. variegate with vague patches of colour. cloud-castle a daydream. cloud chamber a device containing vapour for tracking the paths of charged particles, X-rays, and gamma rays. clouded leopard a mottled arboreal S. Asian feline, Neofelis nebulosa. cloud-hopping movement of an aircraft from cloud to cloud esp. for concealment. cloud-land a utopia or fairyland. in the clouds 1 unreal, imaginary, mystical. 2 (of a person) abstracted, inattentive. on cloud nine (or seven) colloq. extremely happy. under a cloud out of favour, discredited, under suspicion. with one's head in the clouds day-dreaming, unrealistic. cloudless adj. cloudlessly adv. cloudlet n.
[ OE clud mass of rock or earth, prob. rel. to CLOD ]